A Deeper Look at the Proportionality-Turnout Nexus

Evidence that turnout is higher under proportional representation (PR) than in majoritarian elections is overwhelming. Yet previous research has largely failed to explain why. One line of argument maintains that higher turnout under PR is a by-product of larger party systems. However, a larger number of parties has been demonstrated to depress turnout. Alternatively, it is argued that majoritarian electoral systems tend to produce safe seats and that voters have little incentive to turn out there. Thus, uneven turnout over electoral districts due to variable intensities of local competition is made responsible for the lower overall turnout. Empirical evidence on this conjecture is scant. This article scrutinizes the relationship between electoral rules, competition, and turnout with district-level data from 31 national elections. Results from a heteroscedastic model indicate that lower net turnout in majoritarian systems is indeed a consequence of uneven turnout over districts due to variable levels of local competitiveness.