United & Divided: Distinctions in Polarization between Political Elites and the Public

Abstract

This study examines the extent and nature of partisan polarization in American politics since 1992. I assess polarization among political elites using DW-NOMINATE data, rhetorical and policy analyses of party platforms, and a summary of literature regarding media impact on polarization. I assess polarization among average Americans using mostly data from the time series American National Election Studies surveys, with some additional data from Gallup, PEW Research, and other literature. For both, I measure polarization using standard deviation scores and sorting using the difference between the mean scores of Republicans and Democrats. I also distinguish between cognitive polarization (based on policy opinions, e.g. issue positions) and social polarization (based on emotional attachments, e.g. feeling thermometer scores). My analysis shows that there has been significant polarization and sorting among political elites and average Americans, and that the nature of polarization among average Americans is complex. For average Americans, increases in sorting are 2 to 9 times greater than increases in polarization, and increases in social polarization are 2 to 3 times greater than increases in cognitive polarization. Sorting that began following the 1960s Civil Rights Movement seems to be the driving force of this polarization. The overall impact on American politics of this level and type of sorting and polarization seems to be negative, and these trends are unlikely to end without significant political realignment.

Keywords: Political Science, American Politics, Polarization, Sorting, Political Parties, Elections, Voting Behavior, Political Psychology, Social Psychology