The electoral buzz: Rational prospective voting and the politics of the zika epidemic in Brazil

Abstract

This article reevaluates often-made assumptions of retrospective voting and voter irrationality in studies of voting behavior in political contexts colored by haphazard, apolitical events. To do so, it leverages the quasi-random 2015–2016 Zika epidemic in Brazil and the accompanying priming of “women’s issues” relating to infant health to empirically assess whether exposure to the virus increased political support for female candidates in the 2016 Brazilian local elections. Results of difference-in-difference analyses suggest that high incidences of the virus in the months immediately preceding the election increased female candidates’ vote shares. Conflicting with theories of irrational retrospective voting, the results are consistent with an understudied theory of rational prospective voting. Robustness and falsification tests and dubious support for alternative explanations lend additional support to the argument. The research contributes to an elucidation of both the complex calculations underlying voting behavior and the conditions favorable to female candidates’ electoral prospects.