Intraparty Polarization in American Politics
Research shows that elite polarization and mass sorting have led to an explosion of hostility between parties, but how do Republicans and Democrats feel toward their own respective parties? Have these trends led to more cohesion or more division within parties? Using the American National Election Studies time series, we first show that intraparty polarization between ideologically extreme and ideologically moderate partisans is on the rise. Second, we demonstrate that this division within parties has important implications for how we think about affective polarization between parties. Specifically, the distribution of relative affect between parties has not become bimodal but merely dispersed. Thus, while the mean partisan has become affectively polarized, the modal partisan has not. These results suggest polarization and sorting may be increasing the viability of third-party candidates and making realignment more likely.