Choosing a Champion: Party Membership and Policy Platform

We introduce endogenous political parties into the Hotelling-Downs voting framework to model the selection of candidates. First, activists choose which party to join, if at all. Second, party members select a champion for the general election. Third, the electorate median voter determines the (stochastic) general election outcome. Although party members trade off win probabilities candidate location preferences, in equilibrium they vote sincerely, so champions are at party medians. Minimum differentiation is only attained when valence uncertainty vanishes. Otherwise, the electorate median voter is in neither party. Despite asymmetric party and policy positions in equilibrium, electoral successes remain roughly equal.