Primaries and Candidates: Examining the Influence of Primary Electorates on Candidate Ideology

Abstract

Primary elections in the United States have been under-studied in the political science literature. Using new data to estimate the ideal points of primary election candidates and constituents, we examine the link between the ideological leanings of primary electorates and the ideological orientation of US congressional candidates. 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 more extreme Republicans are more likely to win their party’s primary and that Republican and Democratic candidates are responsive to different electoral constituencies.