Ideological Heterogeneity and Voter Turnout

Abstract How does ideological diversity within electoral districts shape voter turnout? We argue that participation is highest at moderate levels of ideological heterogeneity: limited disagreement can make political differences more salient and consequential, while extensive disagreement can generate ambiguity and discourage participation. Using data from 31,246 respondents during the 2015 Canadian federal election and positions on 37 policy issues, we examine this relationship at both the individual and district levels. We find a significant inverted-U relationship between individuals’ ideological distance from their district mean and their likelihood of voting, net of electoral competitiveness and campaign mobilization. District-level turnout exhibits a substantively similar, though statistically less clear, pattern. A cross-level interaction further shows that the individual-level relationship varies with district ideological heterogeneity. These findings demonstrate that turnout is shaped not simply by individual preferences or electoral competition, but by the ideological context in which voters are embedded.