Political Competition in Legislative Elections
by Stefan Krasa, University of Illinois and Mattias K. Polborn, Vanderbilt University
In Congressional elections, voters generally decide not just based on their local candidates’ positions, but they also care about the positions of national politicians and parties, even though they are not explicitly on their ballot. Our article shows that the association between local candidates and national parties reduces or even eliminates the competitive pressure to nominate moderate candidates at the district level. Republicans can win in moderately conservative districts, and Democrats in moderately liberal ones, even if they nominate candidates that are more extreme than most of the voters in these districts would prefer. Moreover, national polarization leads to a vicious cycle, allowing for more and more extreme candidates to win. Gerrymandering is a powerful way to start this vicious cycle, because it generates safe districts in which extreme candidates are guaranteed to win, creating more distance between the national parties. Our model also points out a flaw in previous empirical research on the causal connection between gerrymandering and polarization.