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Leapfrog Representation and Extremism: A Study of American Voters and Their Members in Congress


We consider the relationship between the preferences of American voters and the preferences of the U.S. legislators who represent them. Using an Internet-based, national opinion survey in conjunction with legislator voting records from the 109th and 110th Congresses, we show that members of Congress are more extreme than their constituents, i.e., that there is a lack of congruence between American voters and members of Congress. We also show that when a congressional legislator is replaced by a new member of the opposite party, one relative extremist is replaced by an opposing extremist. We call this leapfrog representation, a form of representation that leaves moderates with a dearth of representation in Congress. We see evidence of leapfrog representation in states and House districts and in the aggregate as well: the median member of the 109th House was too conservative compared to the median American voter, yet the median of the 110th House was too liberal. Thus, the median American voter was leapfrogged when the 109th House transitioned to the 110th. Although turnover between the 109th and 110th Senates occurred at approximately the same rate as between the 109th and 110th Houses, the Senate appears to be a more moderate institution whose median member does not move as abruptly as that of the House.

Corresponding author
Joseph Bafumi is Assistant Professor of Government, Dartmouth College, 6108 Silsby Hall, Hanover, NH 03755 (
Michael C. Herron is Professor of Government, Dartmouth College, 6108 Silsby Hall, Hanover, NH 03755 (
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Abramowitz, Alan. 2010. The Disappearing Center: Engaged Citizens, Polarization and American Democracy. New Haven, CT: Yale University Press.
Abramowitz, Alan I., and Saunders, Kyle L.. 2008. “Is Polarization a Myth?Journal of Politics 70 (2): 542–55.
Achen, Christopher H. 1977. “Measuring Representation: Perils of the Correlation Coefficient.” American Journal of Political Science 21: 805–15.
Achen, Christopher H. 1978. “Measuring Representation.” American Journal of Political Science 22: 475510.
Alesina, Alberto, and Rosenthal, Howard. 1996. “A Theory of Divided Government.” Econometrica 64 (6): 1311–41.
Ansolabehere, Stephen D., Snyder, James M., and Stewart, Charles. 2001. “Candidate Positioning in U.S. House Elections.” American Journal of Political Science 45: 136–59.
Bafumi, Joseph, Erikson, Robert S., and Wlezien, Christopher. 2010. “Balancing, Generic Polls and Midterm Congressional Elections.” Journal of Politics 72 (3): 705–19.
Bafumi, Joseph, Gelman, Andrew, Park, David K., and Kaplan, Noah. 2005. “Practical Issues in Implementing and Understanding Bayesian Ideal Point Estimation.” Political Analysis 13: 171–87.
Bailey, Michael A. 2007. “Comparable Preference Estimates across Time and Institutions for the Court, Congress, and Presidency.” American Journal of Political Science 51 (3): 433–48.
Baron, David P. 1994. “Electoral Competition with Informed and Uniformed Voters.” American Political Science Review 88 (1): 3347.
Black, Duncan. 1958. The Theory of Committees and Elections. Cambridge: Cambridge University Press.
Burden, Barry C. 2004. “A Technique for Estimating Candidate and Voter Locations.” Electoral Studies 23: 623–39.
Calvert, Randall L. 1985. “Robustness of the Multidimensional Voting Model: Candidates' Motivation, Uncertainty, and Convergence.” American Journal of Political Science 29 (1): 6995.
Canes-Wrone, Brandice, Herron, Michael C., and Shotts, Kenneth W.. 2001. “Leadership and Pandering: A Theory of Executive Behavior.” American Journal of Political Science 45 (3): 532–50.
Carson, Jamie L., Crespin, Michael H., Jenkins, Jeffery A., and Wielen, Ryan J. Vander. 2004. “Shirking in the Contemporary Congress: A Reappraisal.” Political Analysis 12 (2): 176–79.
Clinton, Joshua D. 2006. “Representation in Congress: Constituents and Roll Calls in the 106th House.” Journal of Politics 68 (2): 397409.
Clinton, Joshua, Jackman, Simon, and Rivers, Doug. 2004. “The Statistical Analysis of Roll Call Data.” American Political Science Review 98 (2): 355–70.
Converse, Philip. 2006. “Democratic Theory and Electoral Reality.” Critical Review 18 (1–3): 297329.
Downs, Anthony. 1957. An Economic Theory of Democracy. New York: Harper and Row.
Elling, Richard C. 1982. “Ideological Change in the U.S. Senate: Time and Electoral Responsiveness.” Legislative Studies Quarterly 7 (1): 7592.
Enelow, James M., and Hinich, Melvin. 1984. The Spatial Theory of Voting: An Introduction. New York: Cambridge University Press.
Enelow, James, and Hinich, Melvin, eds. 1990. Advances in the Spatial Theory of Voting. New York: Cambridge University Press.
Epstein, David, Herron, Michael C., O'Halloran, Sharyn, and Park, David. 2007. “Estimating the Effect of Redistricting on Minority Substantive Representation.” Journal of Law, Economics, and Organization 23 (2): 499518.
Erikson, Robert S. 1978. “Constituency Opinion and Congressional Behavior: A Reexamination of the Miller-Stokes Data.” American Journal of Political Science 22: 511–35.
Erikson, Robert S., MacKuen, Michael B., and Stimson, James A.. 2002. The Macro Polity. New York: Cambridge University Press.
Erikson, Robert S., and Tedin, Kent L.. 2001. American Public Opinion. 6th ed. New York: Longman.
Fairlie, J. A. 1940a. “The Nature of Political Representation, I.” American Political Science Review 34: 236–48.
Fairlie, J. A. 1940b. “The Nature of Political Representation, II.” American Political Science Review 34: 456–66.
Fiorina, Morris P. 1974. Representatives, Roll Calls, and Constituencies. Lexington, MA: Lexington Books.
Gerber, Elisabeth R., and Lewis, Jeffrey B.. 2004. “Beyond the Median: Voter Preferences, District Heterogeneity, and Political Representation.” Journal of Political Economy 112: 1364–83.
Groseclose, Timothy, Levitt, Steven D., and Snyder, James M.. 1999. “Comparing Interest Group Scores across Time and Chambers: Adjusted ADA Score for the U.S. Congress.” American Political Science Review 93: 3350.
Heckman, James J., and Snyder, James M.. 1997. “Linear Probability Models of the Demand for Attributes with an Empirical Application to Estimating the Preferences of Legislators.” Rand Journal of Economics 28: S142–89.
Herron, Michael C., and Sekhon, Jasjeet S.. 2005. “Black Candidates and Black Voters: Assessing the Impact of Candidate Race on Uncounted Vote Rates.” Journal of Politics 67 (1): 154–77.
Jackman, Simon. 2001. “Multidimensional Analysis of Roll Call Data via Bayesian Simulation: Identification, Estimation, Inference and Model Checking.” Political Analysis 9: 227–41.
Jacobs, Lawrence R., and Shapiro, Robert Y.. 1997. “The Myth of the Pandering Politician.” The Public Perspective 8: 35.
Jacobs, Lawrence R., and Shapiro, Robert Y.. 2000. Politicians Don't Pander: Political Manipulation and the Loss of Democratic Responsiveness. Chicago: The University of Chicago Press.
Jacobson, Gary C. 2007a. A Divider, Not a Uniter: George W. Bush and the American People. New York: Pearson Longman.
Jacobson, Gary C. 2007b. “The President, the War, and Voting Behavior in the 2006 House Elections: Evidence from Four National Surveys.” Presented at the Illinois Conference on Congressional Elections, University of Illinois, Urbana–Champaign.
Jennings, M. Kent. 1992. “Ideological Thinking among Mass Publics and Political Elites.” Public Opinion Quarterly 56 (4): 419–41.
Jessee, Stephen A. 2009. “Spatial Voting in the 2004 Presidential Election.” American Political Science Review 103 (1): 5981.
Keyssar, Alexander. 2000. The Right to Vote: The Contested History of Democracy in the United States. New York: Basic Books.
Kimball, David C. 2003. “Voting Methods Two Years after Florida.” Presented at the Annual Meeting of the Midwest Political Science Association, Chicago.
Lawrence, Christopher N. 2007. “Of Shirking, Outliers, and Statistical Artifacts.” Political Research Quarterly 60 (1): 159–62.
Levendusky, Matthew S., Pope, Jeremy C., and Jackman, Simon. 2007. “Measuring District Level Partisanship with Implications for the Analysis of U.S. Elections.” Journal of Politics. Forthcoming.
Londregan, John. 2000. “Estimating Legislators Preferred Points.” Political Analysis 8 (1): 2556.
Martin, Andrew D., and Quinn, Kevin M.. 2002. “Dynamic Ideal Point Estimation via Markov Chain Monte Carlo for the U.S. Supreme Court, 1953–1999.” Political Analysis 10: 134–53.
Martin, Andrew D., and Quinn, Kevin M.. 2007. “Assessing Preference Change on the US Supreme Court.” Journal of Law, Economics, and Organization 23 (2): 365–85.
McCarty, Nolan, Poole, Keith T., and Rosenthal, Howard. 2009. “Does Gerrymandering Cause Polarization?American Journal of Political Science 53 (3): 666–80.
Miller, James C. III. 1999. Monopoly Politics. Stanford, CA: Hoover Institution Press.
Miller, Warren E., and Stokes, Donald W.. 1963. “Constituency Influence in Congress.” American Political Science Review 57: 4546.
Monroe, Alan D. 1998. “Public Opinion and Public Policy 1980–1993.” Public Opinion Quarterly 62: 628.
Poole, Keith T. 2007. “Changing Minds? Not in Congress!Public Choice 131 (3–4): 435–51.
Poole, Keith T., and Romer, Thomas. 1993. “Ideology, Shirking and Representation.” Public Choice 77 (1): 185–96.
Poole, Keith T., and Rosenthal, Howard. 1997. Congress: A Political-economic History of Roll Call Voting. New York: Oxford University Press.
R Development Core Team. 2009. R: A Language and Environment for Statistical Computing. Vienna, Austria: R Foundation for Statistical Computing.
Saunders, Kyle L., and Abramowitz, Alan I.. 2004. “Ideological Realignment and Active Partisans in the American Electorate.” American Politics Research 32 (3): 285309.
Shor, Boris, and McCarty, Nolan. 2010. “The Ideological Mapping of American Legislatures.” Working paper (August 8, 2010).
Snyder, James M. 1992. “Artificial Extermism in Interest Group Ratings.” Legislative Studies Quarterly 17: 319–45.
Stimson, James A. 1975. “Belief Systems: Constraint, Complexity, and the 1972 Election.” American Journal of Political Science 19 (3): 393417.
Stimson, James A. 2004. Tides of Consent: How Opinion Movements Shape American Politics. New York: Cambridge University Press.
Stimson, James A., MacKuen, Michael B., and Erikson, Robert S.. 1995. “Dynamic Representation.” American Political Science Review 89: 543–65.
Sulkin, Tracy. 2005. Issue Politics in Congress. New York: Cambridge University Press.
Tomz, Michael, and van Houweling, Robert P.. 2003. “How Does Voting Equipment Affect the Racial Gap in Voided Ballots?American Journal of Political Science 47 (1): 4660.
Treier, Shawn, and Jackman, Simon. 2008. “Democracy as a Latent Variable.” American Journal of Political Science 52 (1): 201–17.
Wahlke, John C., Eulau, Heinz, Buchanan, William, and Ferguson, Leroy C.. 1962. The Legislative System: Explorations in Legislative Behavior. New York: John Wiley and Sons.
Wittman, Donald. 1990. “Spatial Strategies When Candidates Have Policy Preferences.” In Advances in the Spatial Theory of Voting, eds. Enelow, James M. and Hinich, Melvin J.. New York: Cambridge University Press, 6698.
Wlezien, Christopher. 1995. “The Public as Thermostat: Dynamics of Preferences for Spending.” American Journal of Political Science 39: 9811000.
Wlezien, Christopher. 1996. “Dynamics of Representation: The Case of U.S. Spending on Defense.” British Journal of Political Science 26: 81103.
Zimmerman, Joseph F., and Rule, Wilma. 1998. “A More Representative United States of Representatives?PS: Political Science and Politics 31: 510.
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American Political Science Review
  • ISSN: 0003-0554
  • EISSN: 1537-5943
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