Polarized Primaries and Polarized Legislators : Examining the Influence of Primary Elections on Polarization in the U.S. House

In this article we develop and test an electoral connection theory of congressional polarization. We theorize that ideologically extreme primary voters are one of the driving forces behind electoral polarization, and polarization among primary voters is reflected in the polarization of party nominees for the House of Representatives. We use district-level data from the Cooperative Congressional Election Study and ideal point estimates for congressional primary election candidates to examine the role of primary electorate ideology in the selection of party nominees. We find that primary voters are more extreme than general election voters, and candidates who run in primary elections with more polarized electorates are likewise more polarized. We also find a significant interaction between extreme primary electorates selecting extreme primary candidates. Finally, we find that Republican and Democratic candidates respond to different electoral constituencies