Abstract
We analyze two-candidate elections in which some voters
are uncertain about the realization of a state variable that
affects the utility of all voters. We demonstrate the existence
of a swing voter's curse: less informed indifferent voters
strictly prefer to abstain rather than vote for either candidate
even when voting is costless. The swing voter's curse leads
to the equilibrium result that a substantial fraction of the
electorate will abstain even though all abstainers strictly
prefer voting for one candidate over voting for another.