Voter Participation with Collusive Parties

We reexamine the theory of rational voter participation where voting is by two collusive parties that can enforce social norms through costly peer punishment. This model nests both the ethical voter model and the pivotal voter model. We initially abstract from aggregate shocks to the population of voters in favor of the original Palfrey and Rosenthal [24] model and analyze the subsequent all-pay auction game. We show that this game has a unique mixed strategy equilibrium in which one party the advantaged party gets all the surplus and give a simple formula for determining which party is advantaged. This equilibrium is scale invariant increasing the size of both parties in proportion has no e ect on voter turnout by either party. Our main nding is that when the cost of enforcement of social norms is low and the bene t of winning the election is the same for both parties the larger party is always advantaged. By contrast, when the enforcement of social norms is costly we have a result reminiscent of Olson [27] in which even if the bene t of winning the election is the same for both parties the smaller party may be advantaged. We then examine more general contest resolution functions giving conditions under which pure strategy equilibria do and do not exist, examining the robustness of the comparative statics of the all-pay auction model, and give conditions under which participation declines with the size of the electorate. JEL Classi cation Numbers: later