The Effects of Import Shocks, Electoral Institutions, and Radical Party Competition on Legislator Ideology: Evidence from France

Abstract Across advanced industrialized democracies, the political centre is collapsing as politicians on the far right and far left enjoy increasing electoral success. Recent research links import shocks to voter support for far-right parties. However, we know comparatively less about how these shocks impact individual legislator ideology, especially that of mainstream politicians. Do import shocks drive economic or cultural ideological shifts among mainstream legislators? If so, to what extent do local competitive contexts shape these shifts? Using a dataset of French Senate roll call votes, we find that localized increases in import exposure moves elite ideology to the left economically; this is magnified in departments with majoritarian electoral systems. We show that legislators shift their cultural positions in response to import shocks, but only when faced with extremist political competitors focused on cultural issues. Our results suggest the value of attending to how political and economic geography intersect to shape elite policy positions.


Introduction
Across advanced democracies, as electorates increasingly opt for populist candidates, the political centre is collapsing.The National Rally in France, the Alternative for Germany, and the Brothers of Italy are among the ever-growing list of right-wing nationalist parties gaining support throughout Europe.At the same time, the voting base of the traditional social democratic left is being bled by radical left competitors such as the France Insoumise and the Left Bloc in Portugal.
Research identifies dimensions of globalization, and localized import shocks in particular, as key determinants of support for populists and rising societal polarization (Autor et al. 2020;Ballard-Rosa, Jensen, and Scheve 2021;Milner 2021) as voters in regions with import influxes increasingly turn to extremist candidates who overwhelmingly emphasize cultural issues (Colantone and Stanig 2018;Margalit 2011).While there is extensive research on demand-side responses to trade on the cultural dimension and work investigating the effects of public opinion on legislator preferences (Colantone and Stanig 2018;Dippel, Gold, and Heblich 2015;Gingrich 2017;Guisinger 2009;Milner and Tingley 2011), we know comparatively less about how import shocks affect politicians (Rodrik 2021;Rommel and Walter 2018), and how they respond to the concurrent emergence of extremist party competition (Abou-Chadi and Krause 2020; Spoon and Williams 2021).
Work on legislative responses to trade is characterized by convergent findings, disagreement, and even silence on key questions.On the one hand, scholars agree that localized import shocks increase negative views about trade and specific trading partners as well as support for protectionism (Campello and Urdinez 2021;Kleinberg and Fordham 2013;Kuk, Seligsohn, and Zhang 2018) and that these effects are stronger among politicians in competitive electoral districts (Feigenbaum and Hall 2015), suggesting electoral incentives also influence legislator ideology.However, scholars disagree about whether trade impacts elite ideology beyond the narrow scope of trade policy (Autor et al. 2020;Feigenbaum and Hall 2015).While trade is one important dimension of economic policy, import shocks also make salient more general economic ideological concerns related to compensation and redistribution.At the same time, an exclusive focus on legislators' economic ideology stands in tension with extensive literature suggesting that trade is closely tied to cultural ideological issues.However, perhaps because the vast majority of studies on legislator responses emerge from the US setting, there have been few efforts to explore how different types of competitive and institutional contexts refract trade-induced dislocations.This is despite general agreement that institutional and competitive contexts should incentivize legislators to respond to economic shocks in distinct ways (Rickard 2018).
This paper asks: do import shocks lead to economic and/or cultural ideological shifts among mainstream legislators?Import shocks are highly localized events that impact some regions of a country while leaving others largely untouched.When representing regions hard hit by imports, mainstream legislators, whose ideology focuses primarily on economic issues, face incentives to shift economically to the left to reflect increased demands for redistribution and compensation (Ruggie 1982;Scheve and Serlin 2023).However, local competitive contextsin the form of varying electoral institutions 1 and the extent of competition from extremist candidates on both the far right and the far leftshould mediate these economic and ideological shifts and, in some cases, force mainstream politicians to adapt their cultural ideology to accommodate the core ideological appeals of their extremist competitors (Meguid 2005).In other words, we argue the effects of import shocks on legislator ideology are contingent on the competitive and institutional contexts in which they operate.
Using an original hand coded dataset of roll call votes from the French Senate, we present three findings of note.First, in line with existing work, we show that localized increases in import exposure drive elite shifts to the left on the economic ideological dimension.Second, these effects are magnified in competitive majoritarian electoral systems.Finally, we find that local variation in radical party strength mediates the effects of import shocks on legislator ideology: a strong radical left presence pulls left-leaning mainstream politicians to the left on both economic and cultural issues, with similar dynamics present on the right.Taken together, our findings contribute to scholarship on the domestic consequences of trade by showing the value of attending to how international forces intersect with localized patterns of political competition to shape the economic and cultural ideologies of elected officials.We also contribute to research on how radical party strength shapes mainstream political actors' behaviour and policy positions.

The Domestic Consequences of Import Shocks
In recent decades, advanced industrialized countries (AICs) have experienced a tremendous increase in trade, labour flows, and finance internationalization.In the aggregate, economic openness can generate significant welfare gains, including overall improvements to industrial productivity (Melitz 2003), higher wages for workers in productive exporting firms (Helpman, Itskhoki, and Redding 2010), employment opportunities for workers that sell their services to foreign customers (Hummels et al. 2014), and consumer access to less costly products (Costinot and Rodríguez-Clare 2014).However, one specific aspect of economic globalizationsudden, 1 For example, majoritarian versus proportional representation (PR) systems.concentrated increases in imports from low-wage countriescarries significant costs for the affected populations in AICs.
Import shocks, which are regionally concentrated, have, over the past twenty years, led to job losses in traditional industries and put substantial downward pressure on wages (Balsvik, Sissel, and Salvanes 2015;Dauth, Findeisen, and Suedekum 2014;Donoso et al. 2014;Malgouyres 2017b).Import flows impact not just workers but also all residents of exposed regions who are concerned about long-term economic decline (Rickard 2022) regardless of their own employment status (Mansfield and Mutz 2009).In these regions, the detrimental effects of imports significantly outweigh the overall gains from trade (Rodrik 2011), and residents in these areas are more likely to emphasize the negative consequences of globalization (Hainmueller and Hiscox 2006).In regions where import competition from low-wage countries is higher, research shows that, on both sides of the Atlantic, voters gravitate toward radical candidates and parties (Colantone and Stanig 2018;Dippel, Gold, and Heblich 2015;Gingrich 2017;Malgouyres 2014;Milner 2021).
Building on this voter-centered work, we ask how legislators representing these regionsand legislators from non-extremist parties, in particularhave changed their policy positions in response to these import-induced dislocations.There is little consensus on how or even whether import shocks affect legislators' ideology (Autor et al. 2020;Butler and Nickerson 2011;Karol 2007;Kleinberg and Fordham 2013;Kuk, Seligsohn, and Zhang 2018).On the one hand, there is some evidence that voters' interests around trade only marginally impact how members of the US Congress vote on legislation (Fordham and McKeown 2003;Guisinger 2009;Hainmueller and Hiscox 2006).Other US studies find local dynamics impact legislative votes, but even here there is disagreement about the scope of these effects.While Feigenbaum and Hall (2015) find trade shocks cause legislators representing affected regions to vote in a more protectionist direction on trade bills alone, Autor et al. (2020) show evidence of a more generalized polarized ideological response.
Interestingly, most research on legislative responses to trade shocks draws on data from the US. 2 What is more, all studies of legislative responses to import shocks of which we are aware analyze a single economic ideological dimension of politics.This economic focus, however, sits in tension with work on how European voters react to trade and globalization.This important literature suggests that rapid import penetration should impact both the economic and cultural dimensions of politics. 3The centrality of the American case has also limited our understanding of scope conditions since key institutional features of the American politya two-party system generated by single-member district electoral rulesare not representative of many other advanced democracies that have been similarly exposed to import shocks.
We advance work on trade and elite ideology by examining the political dynamics of local labour market disruptions in a case outside of the US -France.Like other advanced democracies, France has experienced a dramatic increase in trade from low-wage countries since the early 2 The only exception of which we are aware focuses on Brazil (Campello and Urdinez, 2021).In the European context most elite-centred research on trade focuses on political parties, particularly at the national level (Adams, Haupt and Stoli, 2009;Haupt, 2010;O'Grady and Abou-Chadi, 2019;Scheve and Serlin, 2023), rather than individual politicians.There is substantial work in Europe on individual legislator responsiveness to voters, but this work has been largely limited to stable economic contexts (André, Depauw, and Martin 2015;Bol et al. 2021;Broockman 2013;De Vries, Dinas, and Solaz 2016;Habel and Birch 2019).

3
On the voter side, economic integration has been linked to increased demand for far-right populism (Colantone and Stanig 2018;Dippel, Gold, and Heblich 2015;Gingrich 2017), anti-immigrant sentiment (Autor et al. 2020;Ballard-Rosa, Jensen, and Scheve 2021;Coffé, Heyndels, and Vermeir 2007;Dippel et al. 2017;Malgouyres 2017a), and increasingly authoritarian attitudes among voters (Gidron and Hall 2017;Norris and Inglehart 2019;Werts, Scheepers, and Lubbers 2013).Until recently, the consensus was that identity and values, rather than economic self-interest, drive voters' trade attitudes (Rho and Tomz 2017).Nevertheless, a growing body of scholarship acknowledges the economic effects of globalization vary sub-nationally and argues that the resulting long-term economic dislocations can lead affected individuals to shift their cultural and economic policy preferences (Rickard 2022;Rommel and Walter 2018; Scheve and Serlin 2023).2000s.Moreover, in contrast to the US, France has a polarized, multi-party system and utilizes a range of electoral systems.These features of the French context enable us to answer important questions about how mainstream political elites respond ideologically to import shocks and how these responses are mediated by electoral institutions and the growing presence of extremist political challengers.

Import Shocks, Local Electoral Context, and Legislator Ideology
Politics in Western democracies takes place along two distinct ideological dimensions: the traditional economic divide and an increasingly salient cultural dimension that focuses on social issues such as gender equality, immigration, and European integration (Caughey, O'Grady, and Warshaw 2019;Hooghe and Marks 2018). 4As illustrated in Fig. 1, we distinguish between the economic left and right and use similar terminology for the second dimension, where the cultural right is characterized by anti-immigrant sentiment, authoritarian attitudes, and nationalism, while the cultural left is more multicultural, libertarian, and (internationally) cosmopolitan (Volkens et al. 2020).
In multiparty systems, parties differ with respect to their policy platforms and the relative emphasis they place on economic versus cultural issues, understood in general terms and in response to challenges created by globalization (Haupt 2010).Established mainstream parties on both the left and right focus predominantly on economic ideological issues (Rommel and Walter 2018) around which these parties were originally formed.While the left emphasizes policies to strengthen the welfare state and expand redistribution, the mainstream right advocates market-oriented policies, decreased government spending, and lower taxes (Allan and Scruggs 2004;Benoit and Laver 2007;Schmidt 2010).
The newer niche parties, such as the radical right and the Green parties, tend to reject this class-based orientation of politics, focusing instead on post-materialist issues such as nationalism, immigration, the environment, or regional autonomy (Meguid 2005).Because these parties define themselves primarily along that second cultural dimension, their economic policy positions are often ambiguous; this is especially the case with the far-right (Ennser-Jedenastik 2022; Rovny 2013).To the extent they adopt economic positions, these parties were, historically, on the economic right (Kitschelt and McGann 1995;Kriesi et al. 2012;Minkenberg 2000), but, over time, they have shifted toward the left, adopting a 'welfare chauvinist' platform that advocates increased social protections for natives while excluding immigrants and other non-nationals (Betz and Meret 2012;Lefkofridi and Michel 2014).

Economic Ideology and the Mediating Role of Electoral Institutions
We draw on existing research on domestic responses to economic globalization to derive clear predictions regarding the ideological shifts of mainstream legislators representing regions hard hit by import shocks.Given that politicians from mainstream parties focus primarily on economic issues and building on work showing legislators respond to trade influxes along the economic dimension (Autor et al. 2020;Campello and Urdinez 2021;Feigenbaum and Hall 2015), we expect that, all else being equal, non-extremist political elites' responses to trade shocks will be reflected primarily in economic ideological shifts.There are two economic policy mechanisms available to legislators to address the dislocations created by import shocks: legislators can advocate expanding compensation and/or greater protectionism.While the literature has increasingly argued that both voters (Colantone and Stanig 2018) and (non-European) legislators (Campello and Urdinez 2021;Feigenbaum and Hall 2015) are likely to favour protectionism in response to trade shocks, in the European context, legislators' economic policy responses are more limited.For all European Union (EU) member states, decisions about trade policy are made at the EU level, with the EU Commissioner for Trade acting on behalf of all member states (Nanou and Dorussen 2013).Legislators in EU member states thus have limited influence over trade policy and cannot credibly promise to introduce protectionist measures since voters in these countries are aware politicians' hands are tied on these issues (Hellwig 2014;Meyerrose 2020Meyerrose , 2023)).Therefore, we expect them to favour compensationand redistribution-oriented policy solutions to the dislocations created by import shocks.
Localized import penetration increases economic and employment volatility, which in turn makes voters more likely to demand increased government spending to compensate for these economic dislocations (Rodrik 1998;Ruggie 1982).These demands for compensation make voters more likely to support left-leaning politicians and parties that advocate welfare state expansion and redistribution.Indeed, there is evidence that the economic insecurities created by import shocks have driven affected voters to favour compensatory policies associated with traditional parties on the left (Rommel and Walter 2018;Scheve and Serlin 2023) and left-wing parties and candidates that universally reject neoliberalism, consumerism, and globalized capitalism have become increasingly electorally successful (Bale and Dunphy 2011; Hopkin 2020).This, in turn, has led to greater government spending (Dreher, Sturm, and Ursprung 2008;Garrett 1998;Rodrik 1998) and an expansion of redistributive policies (Bergh and Nilsson 2010;Leibrecht, Klien, and Onaran 2011;Meinhard and Potrafke 2012).
While import shocks directly impact employment outcomes for only a subset of workers within affected regions, the effects of these shocks on voters' economic preferences extend beyond the individual level.Localized trade shocks can trigger sociotropic considerations that influence not just the economic policy preferences of impacted workers but also the preference of all voters in these regions who are concerned with the economic well-being of their community (Rickard 2022).Indeed, there is evidence that awareness of rising unemployment leads many voters in a region, regardless of their employment status, to hold the government accountable for their locality's shifting economic landscape (Mansfield and Mutz 2009).This, in turn, creates incentives for legislators representing these areas to shift their economic ideological position.Therefore, our baseline prediction is: Hypothesis 1: Legislators representing regions exposed to import shocks will shift to the left along the economic ideological dimension.
Where institutions increase incentives for elected officials to be responsive to local demands, the effect of import shocks on legislator ideology should be magnified.Research shows one type of institution in particularthe electoral systemcreates distinct incentives for how politicians respond to local economic conditions (Breunig, Grossman, and Hänni 2022;Chang et al. 2010;Katz 1997;Shugart and Taagepera 1989;Taagepera 1973).Since Duverger (1954), political scientists have highlighted how electoral systems can induce changes in elite ideology through their mechanical effects on vote-seat elasticities.In majoritarian systems, small vote swings can dramatically distort the relationship between votes and seat shares (Rogowski and Kayser 2002).Because identical vote distributions are often translated into different seat allocations, depending on the electoral system, in majoritarian systems (where small vote swings can dramatically distort the relationship between vote and seat shares), alienating voters by failing to offer policies that address the negative effects of import shocks entails a higher risk for politicians (Wlezien and Soroka 2012).
Existing work suggests another channel through which majoritarianism promotes greater responsiveness: the fact that candidates in majoritarian districts can campaign, at least to some extent, on personal characteristics and are thus less dependent on their party for re-election (Carey 2007;Carey and Shugart 1995;Katz 1997;Mitchell 2000).In districts where the incumbency advantage plays a more pivotal role (Hainmueller and Kern 2008), we similarly expect legislators to face greater incentives to respond to trade-generated dislocations, irrespective of the position taken by their political party (Sieberer 2010).
Although majoritarian electoral systems create incentives for greater elite economic ideological shifts in regions hard hit by imports, the literature also suggests the extent to which these electoral incentives influence politicians' strategies is contingent on the competitiveness of the election.According to the 'marginality hypothesis', legislators elected by narrower margins (for example, those in more competitive districts) will be more attentive to voter demands due to the possibility of voter backlash.Indeed, focusing on legislative responses to trade, Feigenbaum and Hall (2015) find that US legislators in competitive electoral districts shift their ideology.Drawing on this research, we predict the following: Hypothesis 2: Legislators from regions exposed to import shocks who are elected via majoritarian rules will shift further to the left along the economic ideological dimension than legislators in proportional representation (PR) systems.These effects should be stronger in the case of competitive majoritarian elections.
While the literature offers clear expectations of how mainstream legislators will respond economically to trade shocks, the extent to which these legislators shift their ideological position with respect to the second cultural dimension is contingent on the political competition they face.We argue that mainstream legislators will be more likely to adjust their cultural positions in response to trade influxes when they face electoral competition from extremist competitors who, as noted above, define themselves primarily with respect to cultural issues rather than economic ones.Absent competitors that make this second dimension salient, legislators will prefer to focus on the economic policy issues central to their political identity.

Incorporating Cultural Ideology: The Role of Extremist Challengers
In representative democracies, elections create incentives for politicians to adjust their ideological positions.However, the nature and context of these elections also influence these incentives.In addition to electoral institutions and the competitiveness of a constituency, the type of competition politicians face should also shape responses to rising import competition (Watson 2015).As extremist parties grow in popular support and, as a result, increase the salience of cultural issues, they pose a direct electoral challenge to mainstream politicians.Indeed, research finds that, when threatened electorally, traditional parties may opt for an accommodative approach wherein they shift their cultural ideology to more closely match that of their extremist competitors in the hopes of drawing in or winning back voters (Meguid 2005).In a direct test of these dynamics, Abou-Chadi and Krause (2020) find mainstream parties are more likely to emphasize anti-immigration positions when the populist radical right received higher vote shares in the previous election.
While work on mainstream party responses to extremists focuses primarily on the far right, the rise of the far left in Europe in recent years suggests a strong radical left presence might similarly influence mainstream elites' policy positions.Building on previous findings to consider individual legislators (rather than parties), we expect mainstream legislators will adopt accommodative strategies when confronted with electoral threats from the far right and the far left.However, the types of threats posed by radical left and right competitors are somewhat distinct.
Populist radical right politicians primarily emphasize second-dimension cultural issues such as immigration.Their stances resonate with working-class voters experiencing significant economic hardship because of globalization, particularly in areas hit hardest by trade (Dippel, Gold, and Heblich 2015;Malgouyres 2014).Given the electoral salience of immigration, politicians across the political spectrum have increasingly advocated anti-immigrant policies to win votes and compete with the far right (Abou-Chadi 2016; Abou-Chadi and Krause 2020; Meguid 2005;Schain 2002;Spoon and Klüver 2020;van Spanje 2010).Therefore, we predict the following: Hypothesis 3: Mainstream legislators in districts with strong far-right competitors will shift to the right on the cultural ideological dimension in response to import shocks.
While the far right defines itself primarily with respect to cultural issues, the far left is more ideologically complex.In Europe, the far left is comprised of both post-materialist niche parties, such as the Greens, who focus primarily on second-dimension issues, and materialist radical-left parties, such as the Communists, who define themselves predominantly with respect to economic topics.Despite having distinct ideological foundations, both far-left parties compete for left-wing voters who have become disenchanted with the mainstream left.In times of economic prosperity, the Greens emphasize their core environmental issues.However, during times of economic hardshipsuch as those that result from import shocks -Communists are particularly successful in attracting voters sympathetic to their economic platforms.In these contexts of economic decline, Green parties shift to emphasizing economic issues to compete with the materialist-oriented far left and attract additional left-leaning voters (Spoon and Williams 2021).Therefore, while we expect far-right competitors to impact a mainstream legislator's cultural ideological position, we anticipate individual politicians from mainstream parties will shift to the left on both the economic and cultural dimensions when confronted with a strong, far-left challenger. 5Formally: 5 Theoretically, whether mainstream politicians shift right or left in response to a strong radical left movement should depend on the radical left's linkages to social organizations (Watson, 2015).We might expect a rightward shift when strong radical left parties are closely linked to 'encapsulating' civil society organizations that render far-left voters electorally unavailable to mainstream centre-left and centre-right parties.Alternatively, when strong, radical-left parties lack these connections to social organizations, there are few disincentives for mainstream left parties to respond to electoral threats on their left flank.We hypothesize a leftward shift in this study because the past thirty years have seen the weakening of both the transmission belt model of PCF-CGT party-union relations and also of municipal socialism (Kriegel 1970;Kriegel, Braun and Muresianu Hypothesis 4: Mainstream legislators in districts with strong far-left competitors will shift to the left on both the economic and cultural ideological dimensions in response to import shocks. Finally, we also evaluate the possibility of differential responses to competitive contexts across partisan identities.Changing ideologies is politically risky for any politician, as it can signal a weak commitment to core principles.Mainstream politicians should only accommodate these extremist positions if they face real and immediate electoral threats; they should be particularly likely to accommodate policy positions closer to their core ideological foundations (Han 2015).Therefore, we expect leftist politicians will be more responsive to a far-left challenger than their mainstream right-wing counterparts, while right-leaning politicians will be more vulnerable to challenges from the far right and respond accordingly.In other words, we predict: Hypothesis 5: Right-wing mainstream politicians will be more responsive to a far-right challenger than their left-wing counterparts.
Hypothesis 6: Leftist mainstream politicians will be more responsive to a far-left challenger than their right-wing counterparts.
To summarize, we predict that, on their own, import shocks will make mainstream legislators more likely to shift their economic ideology to the left, reflecting considerations surrounding redistribution and compensation.However, the competitive context in which these legislators operate should also impact the relationship between import shocks and ideology.First, since majoritarian electoral institutions create incentives for greater responsiveness than PR systems, we expect that legislators elected under majoritarian rules will be particularly likely to shift their economic ideology to the left; this should especially be the case in competitive majoritarian systems.Second, we predict mainstream legislators' ideological shifts in response to import shocks will be influenced by competition from extremist competitors.Specifically, we expect competition from the far right will pull legislators in trade-affected regions to the right on the cultural dimensions, while competition from the far left will induce further shifts to the left on both economic and cultural issues.Right-wing politicians will be particularly responsive to far-right challenges, while left-wing candidates will be more susceptible to challenges from the far left.These predictions are summarized in Table 1.
In testing these hypothesized relationships between import shocks, local competitive context, and legislator ideology, it is important to consider the potential mechanisms driving any observed ideological shifts.On the one hand, movements in legislative ideology could be driven by the election of new legislators that are further to the left/right than their predecessor ('replacement').Indeed, a substantial literature in political economy finds that economic downturns disadvantage incumbent politicians (Brooks and Brady 1999;Lewis-Beck and Paldam 2000), as voters punish incumbents at the polls for the adverse economic outcomes, including those caused by greater trade exposure (Jensen, Quinn, and Weymouth 2017;Margalit 2011;2013).There could also be a selection mechanism at work, as competition for votes induces incumbent politicians in trade-exposed districts to strategically shift their ideological stances in response to changing voter preferences ('realignment').Below, we test the extent to which our results are driven by realignment or replacement dynamics.
1979).With this slow but steady organizational disembedding of communist voters, we believe there are few disincentives for mainstream left parties to respond to electoral threats on their left flank.

The French Senate as a Lens for Studying Legislative Behaviour
We study the dynamics of trade influxes and elite politics in the context of the French Senate.Like many other advanced industrialized countries, France experienced a dramatic increase in imports from low-wage economies beginning in the mid-1990s, and especially from China after it entered into the World Trade Organization (WTO) in 2001, leading to substantial locallevel disruptions to both employment and wages (Malgouyres 2014).Moreover, France has one of the most polarized electorates in Europe, making it an ideal context for exploring how the electoral success of extremist parties impacts individual legislators' ideological positions.Indeed, both the far right and the far left are prominent in French politics, though with significant subnational variations.This allows us to explore how local political geography intersects with trade-generated dislocations to influence the ideology of non-extremist legislators.
The under-studied French Senate also offers a particularly useful setting for exploring how democratic linkages influence elite behaviour.Unlike most legislatures, the Senate employs multiple electoral systems simultaneously, thereby allowing us to test the varying effects of electoral system type on legislator ideology within a single case.6Some French senators are elected via majoritarian rules, others by proportional representation.Approximately two-thirds of senators were elected via majoritarian methods in the period under examination here. 7rench senators are indirectly elected by a 150,000-member electoral college composed of locally-elected officials.Although indirectly elected, important institutional reasons exist to expect these senators to respond to the local concerns of voters.Until 2017, French senators were permitted to hold 'dual mandates' wherein they simultaneously served in the legislature while also holding directly elected local political offices. 8Research suggests legislators holding dual mandates have strong incentives to represent local interests (Bach et al. 2012;Costa and Kerrouche 2009;Page and Goldsmith 2016) and are more likely to feel connected to local grievances (Van de Voorde and de Vet 2020).9Concerns with the consequences of globalization, driven by senators' strong local ties, are encapsulated in the words of former senator, Francis Grignon: Offshoring, deindustrialization, globalization … the decline of France, the economic take-off of China … As senators, the constitutional representatives of the territories who are in many instances also holders of local mandates, we are frequently confronted with the economic difficulties and the human tragedies resulting from the closing of a factory.We know the collective price, the social and economic cost: disarray of families hit by unemployment, immediate effects on the local production of trade and crafts, even industrial subcontractors … dangerous imbalances to which the entire community suddenly finds itself exposed' (Grignon 2004).
Senators' worries about the consequences of import shocks are reflected in their legislative activity.Following China's accession to the WTO, in 2004 the French Senate created a working group on labour dislocations, holding some fifty hearings (Arthuis 2005).That year, the Senate's Committee on Economic Affairs produced a 300-page report roundly criticizing liberal responses to France's employment crisis, advocating instead for a neo-Colberiste strategy in which the EU would coordinate a continent-wide industrial policy (Grignon 2004).The Senate Finance Committee subsequently released a report proposing tax strategies to assist beleaguered firms facing intensified global competitiona theme that remained relevant nearly a decade later. 10 In short, we have theoretical and empirical reasons to believe that French senators should be responsive to local-level labour market developments.Nevertheless, the indirect nature of Senate elections constitutes a hard test for the claim that import competition drives legislative ideological shifts.If we find effects here, they should be even more evident in legislatures where politicians are directly elected.

Dependent Variable: Ideology of French Legislators
We use a spatial model to capture ideological shifts among French senators.Applications of spatial models are extensive in the US Congress (Poole and Rosenthal 1985) but have also been applied in legislatures with more than two political parties (Hix and Noury 2009;Meyerrose 2018). 11However, only a subset of these models allows for the intertemporal comparisons of ideology needed to test our argument regarding shifts in legislative positions over time in response to import shocks.We use a Bayesian dynamic item response (IRT) model to measure senators' ideological changes.The dynamic IRT model, developed by Martin and Quinn (2002), is a more flexible alternative to DW-NOMINATE, another intertemporal spatial model (Poole and Rosenthal 2001).The dynamic IRT model allows individuals' ideologies to change nonmonotonically across legislative sessions (Clinton, Jackman, and Rivers 2004) and produces more precise point estimates than DW-NOMINATE.
Like American senators, not all French senators are elected simultaneously.American politics scholars count each two-year congressional session as a legislative session for the US Senate; we follow a similar strategy.Because French parliamentary sessions only last nine months, we divide the French Senate into sessions coinciding with periods between elections (three years). 12We assign a session ID to each three-year period between the Senate elections during the Fifth Republic.Our sample includes voting data from seven sessions: 13 (1996-1998) through 19 (2014-2017).
To estimate the dynamic IRT model, we scraped and cleaned information on public roll call votes for all but two of the Senate sessions between 1996 and 2017. 13The result is a dataset of 3,589 roll call votes with information on how each senator voted on a given bill and a text-based description of each bill's content.10 See, for example: https://www.senat.fr/seances/s201202/s20120222/s20120222.pdf.11 See Appendix A for an overview of spatial models of voting.
12 For most of the Fifth Republic, one-third of the Senate faced re-election every three years.There are exceptions: for example, a Constitutional Council ruling requires the Senate to have a four-year period between elections (2004 to 2008) to avoid too many elections (National Assembly, local, regional) in a single year.
We predict mainstream legislators representing import-exposed departments will be more likely to shift their economic ideological position to the left and, depending on their local context and partisan attachment, their cultural position to either the left or the right. 14We estimate legislators' ideological positions on a subset of relevant roll call votes to ensure we capture shifts in the economic and cultural dimensions.Drawing on the economic and cultural categories identified in the Comparative Manifesto Project (Volkens et al. 2020), we use the text descriptions to hand code each of the 3,589 bills as either economic, cultural, or neither. 15The result is two mutually exclusive sets of roll call votes: 2,227 economic and 613 cultural.
We validate our hand coding using the Comparative Agendas Project data (Baumgartner et al. 2019), which codes a subset of the bills in our dataset by topic. 16Since we identify relatively few cultural bills, we adopt a model-based approach to validate our codings further.DW-NOMINATE models allow the researcher to define the number of ideological dimensions ex-ante and then use patterns in the data to place legislators along the specified number of dimensions.We estimate a DW-NOMINATE model along two dimensions for the French Senate, finding that the first dimension alone correctly classifies about 95 percent of all roll call votes in our dataset.Although somewhat surprising, this gives us further confidence that our codings, which are heavily skewed toward economic bills, are accurate.
To estimate ideological positions in the French Senate, we apply an approximation of the dynamic IRT model using the emIRT package in R (Imai, Lo, and Olmsted 2016). 17In preparing the data, we follow conventional practices and exclude individual roll call votes for which the vote was either 97.5 percent for or against.We also remove legislators who did not vote at least twenty-five times within a given parliamentary session. 18Finally, given the French Senate's strict legislative voting rules, our view is that abstentions essentially equate to 'nay' votes in this context and we code them as such. 19 The dynamic IRT model requires the modeler to specify a set of prior distributions.We set priors based on a legislator's party affiliation to orient the ideological space.These priors are only used for the first session a senator serves, so they are not overly restrictive.We estimate two IRT models: one for the economic bills and another for the cultural ones. 20We operationalize our dependent variables, economic and cultural ideological shifts, simply as changes in the relevant IRT scores, both at the department and individual senator levels. 21

Independent Variables
To measure trade-induced labour market shocks, we use the shift-share Imports per Worker (IPW) measure pioneered by Autor, Dorn, and Hanson (2013) and Autor et al. (2020) to estimate local-level exposure to imports from China.The intuitive idea behind this approach is that local labour markets are differentially affected by the growth in imports from low-wage countries 14 While our theoretical argument is focused on the ideological responses of mainstream legislators, approximately 8 percent of our sample are from non-mainstream parties, mainly the Communist Party, for whom economic issues are highly salient.Appendix H shows results breaking down responses by type of left party; results are substantively similar.15 Some bills mention economic and cultural issues; for example, some bills discuss equal pay for women and minority groups.In these cases, we code the bill as economic since the primary issue is economic in nature.

16
See Appendix B for a detailed discussion.17 See Appendix A.1 for details.

18
We do not apply these exclusions in the cultural models since our dataset has relatively few cultural bills.depending on their prior industry specialization.Any changes in imports at the industry level will disproportionately impact areas with higher degrees of employment in that industry.
As Fig. 2 shows, there is a substantial geographic variation with respect to trade exposure in France.Here, we see import competition in France operates on roughly a southwestern to northeastern axis.Departments in the northeast have been particularly hard hit.In contrast, the southwestern regions, less intensive in import-competing industries, have far lower IPWs.
Following previous studies, we address the possible endogeneity of legislative voting patterns to the import shock by instrumenting IPW using the growth in imports from China to five other wealthy European countries: Germany, Denmark, Sweden, Italy, and the UK (Dauth, Findeisen, and Suedekum 2014). 22 Our other main independent variables of interest relate to local context: electoral institutions, electoral competitiveness, and patterns of party competition.We use French Senate election data to construct measures indicating whether a department held elections under majoritarian (as opposed to PR) electoral rules, as well as constituency-level vote margins and radical party vote share measures from the prior election. 23In addition to our main independent variables, and as shown in Table 2, our models include a measure of the start-of-period political tendency of the department, as well as controls for demographic and economic factors, including a department's start-of-period logged total population, percent female, age structure, percent immigrant population, and percent employed in industry.This data was obtained from INSEE's Estimations de Populations.We also estimate models with two sets of political controls.The first includes a

22
See Appendix D for a description of the IPW measure and the instrument.We also include robustness checks usinga broader range of less developed countries to generate the IPW measure and the instrument; results remain substantively unchanged.
measure of department-level competitiveness, department magnitude, degree of local office holding, and an indicator for a majoritarian electoral system.We also include models that control for other changing features of the political context that might affect legislative behaviour, including indicators for whether, in a particular session, a department experienced a change in its electoral system, there was an expansion of seats, senators in a department were up for re-election in the subsequent session, and if the legislature was divided.
Finally, for all models, we include two-way unit and time-fixed effects, 24 and we report heteroskedasticity-robust standard errors clustered at the region level to account for spatial autocorrelation.In Appendix L, we report full regression tables, including F-statistics based on robust to weak instrument tests (Pflueger and Wang 2015).

Estimation Strategy
To estimate the relationship between trade exposure and legislative behaviour, we follow standard practice by adopting a first-differences model, which allows us to control for time-invariant heterogeneity: where it refers to department i from time t to t + 1.We defined ΔIPW it previously.ΔIRT it refers to the change in the department ideology score from time (session) t to t + 1. X it indicates a series of departmental start-of-period political and demographic controls, while ε it is an idiosyncratic shock we assume is uncorrelated with the regressors.We examine changes in import exposure and its effect on legislator ideology across all elections in our sample.We generate session-by-session IPW measures, IRT scores, and start-of-period controls for each department.This gives us five time periods: the change in trade exposure and legislative ideology from Senate sessions 13 to 14, sessions 14 to 15 and so on, up through session 19.We then pool the data and use stacked first-difference estimation to examine the effects of short-term shifts in localized trade exposure on changes in legislator ideology. 25

Overall Results
We first examine the effects of changes in trade exposure on legislator economic ideology to test Hypothesis 1 by estimating, in Fig. 3, two-stage least squares (2SLS) models in which the We include senator fixed effects for individual models and department fixed effects for department models.

25
We note that our analysis should not be viewed as estimating the total impact of trade openness on legislator ideology since, as discussed in Section 'The Domestic Consequences of Import Shocks', trade openness can have both positive and negative economic effects.Rather, the findings reported below capture the localized political effects of one particularly salient aspect of trade:import shocks.Nevertheless, in Appendix J, we report additional models that account for potentially positive effects of trade.The results remain substantively similar.dependent variable is a change in economic ideology. 26We report instrumental variable estimates using both individual-and department-level datasets.As noted above, analyzing within-senator changes provides insight into how changes in IPW affect the ideology of incumbent senators, while within-department changes capture shifts in the average ideological disposition of the department via the election of new senators.These two sets of models assess the mechanisms driving ideological shifts by capturing the degree to which change is driven by ideological realignment among sitting senators (individual models) and/or replacement by newly elected senators (department models).
In Panel A of Fig. 3, we examine the effects of trade on individual-level economic IRT scores. 27As Hypothesis 1 predicts, the results show a significant leftward shift among incumbent senators in response to localized increases in import exposure.A shift in imports per worker from the 25th to the 75th percentile results in a leftward shift in economic ideology of approximately one-third of a standard deviation.This suggests that leftward shifts are driven, at least in part, by realignment among sitting senators.
Next, we turn to the department-level models in Panel B of Fig. 3.In our data, approximately one-third to one-half of senators are replaced in any given renewal, making a replacement dynamic plausible. 28At the department level, we find greater trade exposure produces a substantively larger ideological shift to the left when compared to the individual-level models. 29lthough the confidence intervals are wider, the coefficients on ΔIPW are approximately four Note: Independent variable is imports per worker, measured in hundreds of euros.All models were estimated using 2SLS.

26
In the figures, we report only the coefficients for the central variables of interest: change in imports for workers and, for the interaction models, majoritarianism or radical party strength.See Appendix L for full regression tables.times larger (−12 versus −3) for the department level as opposed to the senator-level models.This suggests that newly elected senators from trade-affected departments tilt substantially more to the left economically than do their incumbent counterparts.Replacement, in addition to ideological realignment, appears to be an important mechanism in explaining this leftward shift on economic issues.

Heterogeneous Effects: Import Shocks and Local Context
The previous section presented results suggesting legislators are responsive to localized trade increases on economic issues.The overall finding on the economic dimension provides comparative evidence consistent with Ferrara and Herron's (2005) analysis of the leftward shifting consequences of trade for legislative behaviour and supports our Hypothesis 1.However, one advantage of our study is that we can explore the conditions under which import shocks are more or less likely to influence legislative outcomes.This brings us to our second major question: the intervening effects of varying electoral institutions and local competition from extremist candidates.In this section, we investigate the consequences of both sets of intervening variables.

The Mediating Effect of Electoral Institutions
As discussed in reference to Hypothesis 2, assuming reasonable levels of electoral competition, we expect the economic ideological effects of trade to be magnified in departments where senators are elected using majoritarian rules.To test this prediction, we report estimates from two sets of models.The first focuses on within-senator responses to import shifts, while the second reports department-level effects.Coefficients for the senator-level models are shown in Figs 4a and 4b. Figure 4a suggests that, overall, majoritarian electoral institutions have little effect on changes in economic ideology above and beyond the effects of trade.Figure 4b explores whether the effects of majoritarianism are contingent on the degree of electoral competition by reporting coefficients for the interaction of ΔIPW, majoritarianism, and department vote margin at different levels of electoral competitiveness.For the within-senator models, as political competition tightens in majoritarian districts, the senator's economic ideology shifts to the left in response to higher levels of import competition, providing support for Hypothesis 2.
The models reported in Figs 4a and 4b analyze the response of sitting senators but do not consider how the election of new senators shapes ideological shifts within departments.We investigate these dynamics with department-level models, reported in Figs 4c and 4d. Figure 4c shows that as import penetration increases in majoritarian departments, the average economic ideology score of the department shifts further to the left compared to PR departments.Figure 5 shows the marginal effects of the fully saturated model.Interestingly, however, Fig. 4d shows this leftward shift takes place irrespective of the electoral competitiveness of the department.The finding that majoritarianism induces a leftward response, even under low levels of electoral competition, suggests the effects of electoral systems in this context may work not simply through what Duverger (1954) termed the 'mechanical' channel of vote-seat shares but also through a 'psychological' channel involving strategic coordination by parties and/or voters over candidate selection.We briefly explore these dynamics in Appendix E and return to this possibility in the conclusion.

How Radical Party Competition Matters
Finally, in Hypotheses 3 and 4, we predict that mainstream legislators will adopt accommodative strategies when confronted with electoral threats from extremist competitors from both the far right and the far left.Figure 6 begins to explore these dynamics, reporting coefficients on models interacting ΔIPW with the electoral strength of radical left and radical right parties in the previous Senate elections in each department. 30esults shown in Fig. 6a suggest that in departments with a pre-existing strong radical left, increases in IPW produce an overall modest leftward shift in economic ideology and a small leftward shift in cultural ideology.By contrast, Fig. 6b suggests that as local political support for the radical right increases, higher levels of import exposure shift the ideology of sitting senators to the right.This effect is particularly strong on the economic dimension but also notable on the cultural one.
Since dramatically changing political ideology is risky for any politician, we also predicted in Hypotheses 5 and 6 that mainstream senators on the right will be more responsive to challengers from the far right, while mainstream left senators will be more likely to accommodate competitors from the far left.To further explore these heterogenous treatment effects by party, in Fig. 7, we re-estimate the models from Fig. 6, but this time, we break out responses by party family with several noteworthy findings.First, Figs 7a and 7b find support for Hypothesis 6: mainstream senators on the left representing departments with a higher radical left vote share adopt accommodative strategies, shifting further to the left on economic and cultural dimensions. 31Similarly, as predicted in Hypothesis 5, in Figs 7c and 7d, we find far-right competitors only significantly impact the economic and cultural ideology of right-leaning mainstream senators, while the results for left-leaning politicians are statistically insignificant.
We note the results in Figs 6b and 7c were unexpected.As outlined in Table 1, we did not predict the far right, which defines itself primarily with respect to second-dimension issues, to affect the economic ideology of any mainstream senators.Since this effect is driven by rightleaning mainstream senators, it is perhaps unsurprising that these senators would be willing to shift their economic and cultural positions to compete with the far right since this would not constitute a large change from their core positions.However, the direction of the shift is also puzzling since, as noted in Section 'Import Shocks, Local Electoral Context, and Legislator Ideology', the National Rally and other far-right parties in Western Europe have, over time, become associated with left-leaning economic platforms that emphasize welfare chauvinism.However, this shift to the economic left is a relatively recent phenomenon, precipitated by the fallout from the 2008 financial crisis (Mudde 2016).Prior to the 2010s, and thus during much of the time period   covered in our analyses, most scholars argue that far-right parties in Western Europe adopted economically right-wing and neoliberal platforms (Kitschelt and McGann 1995;Kriesi et al. 2012;Minkenberg 2000) that more closely align with the economic ideology of the mainstream right.

Conclusion
There now exists substantial evidence of globalization's far-reaching domestic consequences at the mass level, but less about the extent to which these effects are reflected at the elite level.Focusing on one aspect of globalization in particular, we ask: do import shocks lead to ideological shifts among individual legislators?Analyzing voting data from the French Senate between 1996 and 2017, we find increases in trade exposure result in a leftward economic shift at both the individual senator-and the constituency-(department) level.Leftward shifts are larger at the department level, suggesting that a replacement mechanism is at work, as sitting senators are replaced by more left-leaning senators in trade-affected departments.We also show ideological shifts on the economic dimension are stronger in competitive majoritarian districts.Finally, we present evidence that the local competitive context in which elections occur mediates the effects of trade: left and right mainstream politicians respond differently to trade in the face of strong extremist competitors.
How do our results relate to existing findings about the political consequences of trade shocks among political elites?The previous literature, much of it coming from the US context, has generated somewhat conflicting findings.While Autor et al. (2020) show these shocks lead to increased economic polarization, other studies report a link between constituency-level import shocks and legislator support for left-leaning legislation.Our results are consistent with the latter, but there remain important differences of emphasis.For example, Feigenbaum and Hall (2015), Kuk, Seligsohn, and Zhang (2018), and Kleinberg and Fordham (2013) find trade generates support for leftward shifts on specific economic issues, such as (protectionist) trade legislation or roll call voting and bill sponsorship activity on legislation hostile to China.By contrast, we find evidence of a generalized economic ideological shift to the left.Because jurisdiction over trade policy lies with the EU in Europe, we cannot make direct comparisons with prior studies on whether import penetration influences the specific issues of protectionism and trade with China.Nevertheless, French Senate reports from this period criticizing the EU's trade policy provide suggestive evidence of rising protectionist inclinations.32Future studies of legislative behaviour around trade policy at the EU level could yield important insights on this question.
Our findings relating to electoral systems also suggest the value of analyzing comparative cases that provide new analytic leverage.Existing work on the elite political consequences of import penetration comes from the US and Brazil, countries with majoritarian and open-list PR electoral systems, respectively.And yet, more than half of the world's legislatures use a different system for aggregating votes into seats: closed-list PR (Cruz, Keefer, and Scartascini 2020).Our study enables us to directly compare ideological responses under majoritarian and closed-list PR systems.The substantially weaker effects in departments with PR elections suggest the possibility of more muted elite responses to trade in many advanced democracies.
Another important question is how our micro-level findings relate to political dynamics in France and elsewhere.The broad leftward economic shift we identify is consistent with existing accounts of the evolution of French economic policy prior to the 2010s, which has been characterized as one of 'social anaesthesia' (Levy 2008), highlighting the fact that state authorities were expanding labour market and social welfare programmes to pacify the victims of economic liberalization.After 2010, the picture becomes more complex.On the one hand, the state moved to liberalize the labour market and rationalize some welfare programmes (Howell 2018).
Nevertheless, this shift toward 'uncompensated liberalism' faced substantial political resistance (Vail, Watson, and Driscoll 2023), and presidents from both the left and the right chose to push through major liberalizing reforms via executive fiat rather than through normal legislative channels (Levy 2023).
At first glance, our findings relating to the cultural dimension of politics stand in some tension with research from both the French and broader European context.Overall, we find that a rise in import competition causes an ideological shift to the left on economic issues but has little effect on cultural ideology.It is only in contexts where mainstream legislators face strong radical party competition that they alter their cultural positions.How does this finding square with common characterizations of France as a case in which globalization has voters actively rewarding the far right and in which there exists a growing hostility to European integration and 'globalism'?Some of the seeming disjuncture may be driven by the fact that France's institutional structure historically made it difficult for the far right to gain a political foothold. 33Despite being a strong contender in the 2002, 2017, and 2022 presidential elections, a prominent force in municipal elections, and winning close to one-quarter of France's seats in the 2014 and 2019 European Parliament elections, the Front National (FN) has been historically underrepresented in national legislative politics.
Rising support for nativism and anti-globalism in response to trade exists in many other Western democracies beyond France (Colantone and Stanig 2018;Dippel, Gold, and Heblich 2015;Gingrich 2017;Malgouyres 2014).And yet, as Rodrik (2021) observes, there is a paucity of work on the relationship between globalization, party-political dynamics, and the emergence of sociocultural cleavages (Rodrik 2021).Our paper offers one possible answer to this ongoing dialogue about the disconnect between mainstream elite (economic) and voter (cultural) responses to globalization: mainstream elites will respond to cultural demands, but only when the dynamics of party competition incentivize them to do so.Returning to the French case specifically, in light of the recent breakthrough of the Front National (now the National Rally) into national legislative politics, we expect mainstream politicians will respond with more accommodation on the cultural dimension in the future.
Finally, although we explore in a preliminary fashion one potential channel through which legislator ideological changes occurvia the dynamics of realignment and/or by electoral replacementimportant questions remain.For example, in several of our department-level models, we find evidence of stronger ideological shifts among newly elected as opposed to sitting senators.This raises additional questions about how globalization affects underlying supply-side dynamics, especially those related to candidate entry and selection.Do rising rates of import penetration affect the ideological leanings of new candidates?If so, how?To what degree does intensifying import competition heighten incentives for parties and voters to respond strategically to the anticipated effects of electoral rules by, for example, presenting fewer candidates in majoritarian elections (Blais and Indridason 2007;Cox 1997;Crisp and Demirkaya 2020;Duverger 1954)?Investigating these and other related questions should offer important insights into the mechanisms through which contemporary global economic forces impact the very functioning of the supply side of the political market.
Supplementary material.The supplementary material for this article can be found at https://doi.org/10.1017/S0007123423000662.
Data availability statement.Replication data for this article can be found in Harvard Dataverse at: https://doi.org/10.7910/DVN/FXRQUJ.Milada Vachudova, the reviewers and editors at BJPolS, contributors at APSA, CES, IPES, MPSA, and ISA conferences, as well as participants in workshops at the Max Planck Institute, Humboldt University, and Princeton University.
Financial support.We gratefully acknowledge grant support from Ohio State University's Mershon Center for International Security Studies.

Figure 1 .
Figure 1.Politics in Western democracies takes place along two distinct ideological dimensions: the economic dimension and the cultural one.

19
See Appendices A.2 and A.3 for a review of the literature on the treatment of abstentions in roll call voting and a discussion of the French Senate's voting rules.20 We report the mean IRT score by party in Appendix B. 21 As discussed in Section 'Incorporating Cultural Ideology: The Role of Extremist Challengers' and below, distinguishing between department and individual-level shifts allows us to test the mechanisms, namely, if realignment or replacement dynamics are driving any observed ideological shifts in trade-exposed regions.

Figure 2 .
Figure 2. Change in Trade Exposure, 1996-2017.This map depicts changes in imports per worker from China in each of France's 95 metropolitan departments disaggregated across 38 employment sectors (NA A38).Source: COMEXT and INSEE.

Figure 3 .
Figure 3. Changes in Imports Per Worker and Ideology (Economic Dimension).

27
Controls are identical in the individual senator-level and department-level models.28Electoraldefeats, retirement, and leaving for positions in the National Assembly or the government are among the most common reasons for replacement.

Figure 4 .
Figure 4. Imports, Electoral Systems and Competitiveness: Senator vs Department-Level Models.Note: For Figs 4a and 4c, the plots report the coefficient on ΔIPW interacted with majoritarianism.Model 1 (top) includes economic and demographic controls (as defined in Table 2); Model 2 (middle) adds political controls A; and Model 3 adds Political controls B. Figs 4b and4dreport coefficients on the interaction of ΔIPW, majoritarianism and the vote margin of a department, at different levels of vote margin, using the full set of controls (i.e., Model 3).All models include unit and session fixed effects.

Figure 5 .
Figure 5. Imports and Electoral Systems: Marginal Effects for Department-Level Models.Note: Marginal effects for change in IPW × Majoritarianism using the full set of controls (economic + demographic controls, plus political controls A and B).

Figure 6 .
Figure 6.Imports and Radical Party Strength: Overall Results.

Figure 7 .
Figure 7. Imports and Radical Party Strength By Party Family.

Table 1 .
Summary of Predictions

Table 2 .
Models and Variables