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¹⁸ Oskarson, ‘Social Structure and Party Choice’. Thomassen, ed., The European Voter, contains data on the United Kingdom, Germany, Netherlands, Sweden, Norway and Denmark.

¹⁹ See Evans, The End of Class Politics?

²⁰ See Bartolini, The Political Mobilization of the European Left. Indeed, working-class support for the left may be regarded as an historical consequence of union penetration in leftist parties, thus creating a link between group identity and political support. See, for example, Mair, Peter, Party System Change: Approaches and Interpretations (Oxford: Oxford University Press, 1998)CrossRefGoogle Scholar.

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²⁵ On the catch-all party, see Kirchheimer, Otto, ‘The Transformation of the Western European Party Systems’, in LaPalombara and Weiner, eds, Political Parties and Political Development, pp. 177–200Google Scholar. On the rational-efficient party, see Wright, William, A Comparative Study of Party Organization (Columbus, Oh.: Charles Merrill, 1971)Google Scholar. On the electoral-professional party, see Panebianco, Angelo, Political Parties: Organization and Power (Cambridge: Cambridge University Press, 1988)Google Scholar. On the cartel party, see Katz, Richard and Mair, Peter, ‘Changing Models of Party Organization and Party Democracy: The Emergence of the Cartel Party’, Party Politics, 1 (1995), 5–28CrossRefGoogle Scholar. On the crisis of the mass party and party failure, see Lawson, Kay and Merkl, Peter, eds, When Parties Fail: Emerging Alternative Organizations (Princeton, N.J.: Princeton University Press, 1988)CrossRefGoogle Scholar.

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³² Most studies over time have held constant the political factors, since party system change of this type is relatively rare in mature democracies, and examined change in society.

³³ The surveys used are Istituto per le Ricerche Statistiche e l'Analisi dell'Opinione Pubblica – Doxa, 1963 survey; Mass Election Study, 1968 and 1972; Political Action Study 1975; Eurobarometer, 11 (1979); Four Nation Study, 1985; Italian National Election Study (ITANES), 1990, 1992, 1994, 1996, 2001, 2006, 2008. For each survey N varies between a low of 705 (in 1992) and a high of 2,400 (in 1968). Average sample size per survey is 2,300.

³⁴ Budge, Ian, Klingemann, Hans-Dieter, Volkens, Andrea, Bara, Judith and Tanenbaum, Eric, Mapping Political Preferences: Estimates for Parties, Electors, and Governments 1945–1998 (Oxford: Oxford University Press, 2001)Google Scholar.

³⁵ We wish to thank Nicolò Conti (CIRCaP-Università di Siena), the author of the content analysis of the 2006 and 2008 coalitions’ manifestos, who generously shared with us his own research.

³⁶ This study was originally directed by Giovanni Sartori, and later by Maurizio Cotta and Luca Verzichelli at CIRCaP-Università di Siena. Samples of representatives from each legislature have been surveyed to collect data on the political careers and political attitudes of MPs over time. We thank CIRCaP for making available this unique data source. The usual disclaimer for responsibility of analysis and interpretation applies.

³⁷ Bartolini and Mair, Identity, Competition and Electoral Availability. See Note to Appendix Table A for explanation of abbreviations of party names.

³⁸ The exact question wordings for the vote have changed somewhat over time. When a vote question was not available (1963, 1975), we relied on party closeness. Although the marginal distribution of these variables is somewhat different, the association between class and religion is not.

³⁹ There are a number of ways in which class can be measured; see Erikson, Robert and Goldthorpe, John, The Constant Flux: A Study of Class Mobility in Industrial Societies (Oxford: Clarendon Press, 1992)Google Scholar. However, earlier research suggests that in Italy the most salient distinction is between manual and non-manual occupations. See Bellucci, ‘Un declino precocemente annunciato?’

⁴⁰ Laver, Michael and Budge, Ian, eds, Party Policy and Government Coalitions (London: Macmillan, 1992)CrossRefGoogle Scholar.

⁴¹ Right Emphasis: Sum of sentences belonging to the following categories: 401 Free Enterprise; 402 Incentives; 407 Protectionsim; 414 Economic orthodoxy. Left Emphasis: Sum of sentences belonging to the following categories: 403 Market Regulation; 404 Economic Planning; 406 Protectionsim; 412 Controlled Economy; 413 Nationalization.

⁴² Bartolini and Mair, Identity, Competition and Electoral Availability.

⁴³ See, for example, Lipset et al., ‘The Psychology of Voting’; Hibbs, Douglas A. Jr, The Political Economy of Industrial Democracies (Cambridge, Mass.: Harvard University Press, 1987)CrossRefGoogle Scholar; Oskarson, ‘Social Structure and Party Choice’. For a full description of the variables used in the analysis see Budge et al., Mapping Political Preferences.

⁴⁴ See Evans et al., ‘Class: Labour as a Catch-all Party?’ We also computed bloc position by applying a fixed weight based on parties average vote share across each republic. The two measures correlate highly (Pearson R = 0.92).

⁴⁵ Since there are only two indicators available to measure religious–secular issues we must treat the results with a certain degree of caution since it is possible that we have not been able to measure the full range of the concept.

⁴⁶ See Lieberson, Stanley, ‘Rank-sum Comparisons between Groups’, Sociological Methodology, 7 (1976), 276–291CrossRefGoogle Scholar.

⁴⁷ For 1979 we lack data on church attendance, and so impute the missing data from an item on the importance of religion. However, the results from this are not substantially different to what they would have been if we had used data on church attendance from earlier (1978) or later (1980) years.

⁴⁸ The party bloc positions on the Secular–Religious Index range between +/− 4 mentions, while those on the Left–Right Index range between −10/+20 mentions.

⁴⁹ For the political salience of this divide, see Isernia, Pierangelo, ‘Bandiera e risorse. La politica estera negli anni ottanta’, in Maurizio Cotta and Pierangelo Isernia, eds, Il gigante dai piedi d'argilla (Bologna: il Mulino, 1996), pp. 139–188Google Scholar.

⁵⁰ Pelizzo raises doubts about the Party Manifesto Data's ability to correctly identify parties’ positions in the political space, particularly in the Italian case. See Pelizzo, Riccardo, ‘Party Position or Party Direction? An Analysis of Party Manifesto Data’, Western European Politics, 2 (2003), 67–89CrossRefGoogle Scholar; and Pelizzo, Riccardo, ‘Party Direction: The Italian Case in Comparative Perspective’, Party Politics, 1 (2010), 51–67CrossRefGoogle Scholar. Pelizzo argues that, rather than indicating position, manifestos indicate movement, and that parties use manifestos to adjust their policy position in order to attract voters. We agree with this interpretation, and are thus more interested in whether the party blocs move towards each other or away from each other, rather than where they stand per se.

⁵¹ Positive values indicate that there are higher levels of organizational mobilization in the centre, negative values indicate higher levels of mobilization on the left.

⁵² See Verzichelli, Luca , ‘Da un ceto parlamentare all'altro. Il mutamento del personale legislativo italiano’, in Roberto D'Alimonte and Stefani Bartolini, eds, Maggioritario finalmente? La transizione elettorale 1994–2001 (Bologna: Il Mulino, 2002), pp. 319–361Google Scholar.

⁵³ The logits that are presented in Figs. 8–10 are, for each election, the log odds of voting centre-right (rather than centre-left) for, respectively, the Secular Middle Class, Catholic Working Class and Catholic Middle Class in relation to the Secular Working Class (reference category).

⁵⁴ This is in essence a variant of the two-step hierarchical regression approach proposed by Achen; see Achen, Christopher, ‘Two-step Hierarchical Estimation: Beyond Regression Analysis’, Political Analysis, 13 (2005), 447–456CrossRefGoogle Scholar.

⁵⁵ We do not include the parent term for the IND since we have no theoretical expectation about the effect of organizational linkages on party vote share, only about the effect on cleavage voting.

⁵⁶ The Kappa index is a summary measure of the variation in cleavage voting between groups. It is based on the standard deviation of the log odds. See Hout, Michael, Brooks, Clem and Manza, Jeff, ‘The Democratic Class Struggle in U.S. Presidential Elections: 1948–1992’, American Sociological Review, 60 (1995), 805–828CrossRefGoogle Scholar. To save space we do not report the findings in a table, but calculations are available upon request from the authors.

⁵⁷ See Parisi, Arturo and Pasquino, Gianfranco, ‘Relazioni partiti-elettori a tipi di voto’, in Arturo Parisi and Gianfranco Pasquino, eds, Continuità e mutamento elettorale in Italia (Bologna: Il Mulino, 1977), pp. 215–249Google Scholar; Mannheimer, Renato and Sani, Giacomo, Il mercato elettorale. Identikit dell'elettore italiano (Bologna: Il Mulino, 1987)Google Scholar.

⁵⁸ See Bellucci, Paolo, Maraffi, Marco and Segatti, Paolo, ‘Intermediation through Secondary Associations: The Organizational Context of Electoral Behaviour’, in Richard Gunther, José Montero and Hans-Jürgen Puhle, eds, Democracy, Intermediation and Voting on Four Continents (Oxford: Oxford University Press, 2007), pp.135–182CrossRefGoogle Scholar.