Party polarization and the rise of partisan voting in US House elections

Most explanations for the increased effect of partisanship on voting for the U.S. House focus on the polarization of parties at the elite levels of politics. It remains unclear, however, just how the two phenomena are connected. In this study, we find that partisans near the extreme of their respective party's prevailing ideology have largely been responsible for the change in voting behavior, because it is these voters who have experienced the greatest increase in relative ideological closeness to the party at the same time that the ideological component of party identification has become a more powerful determinant of electoral choice. There is little support, however, for the idea that partisan realignment by moderately liberal Republicans and moderately conservative Democrats in response to perceptions of growing divergence between the parties has been the mechanism behind elevated party-based voting.