Uncontested incumbents and incumbent upsets

Abstract

This paper presents a model of elections that explores the relationship between incumbent upsets and incumbents running unopposed. A valence-disadvantaged candidate (a potential challenger), who possesses private information about the extent of this disadvantage, first decides whether to challenge a valence-advantaged candidate (the incumbent). If the election is contested, the two candidates engage in policy competition. In equilibrium, the incumbent is never certain of the strength of a challenger she faces, and she may risk losing by proposing a less moderate policy for the possibility of winning at a policy more to her liking. The model demonstrates that analysts risk mischaracterizing candidate behavior by ignoring the possibility that an advantaged candidate may lose due to “rational complacency.” Key comparative statics may switch signs if analyses exclude uncontested elections, and reducing the frequency of uncontested elections entails the trade-off for voter welfare of more extreme platforms in contested elections.