Abstention and political competition

The classical literature on spatial majority voting postulates that all citizens vote. The Median Voter Theorem (MVT) then obtains when parties have perfect information on voter behavior and are either office-seekers (“Downsian”) or ideological. This paper introduces abstention, a simple yet realistic modification. We show that the main features of the MVT survive to a large extent but subject to some qualifications. First, the winning policy does not bear any necessary relation to the median voter. Second, there exist examples in which the candidates choose different positions at equilibrium. Third, equilibrium may fail to exist or be unique. Finally, the equilibria of the model with office-motivated parties may differ from the ones where parties are ideological. Received: 18 September 1999 / Accepted: 31 January 2000