One Person,Many Votes: Divided Majority and Information Aggregation

This paper shows that information imperfections and common values can solve coordination problems in multicandidate elections. We analyze an election in which (i) the majority is divided between two alternatives and (ii) the minority backs a third alternative, which the majority views as strictly inferior. Standard analyses assume voters have a fixed preference ordering over candidates. Coordination problems cannot be overcome in such a case, and it is possible that inferior candidates win. In our setup the majority is also divided as a result of information imperfections. The majority thus faces two problems: aggregating information and coordinating to defeat the minority candidate. We show that when the common value component is strong enough, approval voting produces full information and coordination equivalence: the equilibrium is unique and solves both problems. Thus, the need for information aggregation helps resolve the majority's coordination problem under approval voting. This is not the case under standard electoral systems.     

WHY VOTE FOR LOSERS?

Voting theory generally concludes that, in first‐past‐the‐post elections, all votes should go to effective candidates (Duverger's Law), and parties should adopt a similar platform (median voter theorem). However, such predictions are not always met in practice. We show why divergence and vote dispersion is a natural outcome when (a) parties are opportunistic, (b) there is uncertainty on the position of the median voter and (c) elections are repeated. “Voting for losers” increases the informational content of elections, and may induce mainstream parties to relocate towards extremists. As a result, to maximize their probability of being elected, they do not adopt median platforms, but instead diverge to a certain extent. (JEL: D72, D81)