This paper presents a goal-oriented model of political participation
based on two psychological assumptions. The first is that people are
more altruistic towards individuals that agree with them and the second
is that people’s well-being rises when other people share their
personal opinions. The act of voting is then a source of vicarious
utility because it raises the well-being of individuals that agree with
the voter. Substantial equilibrium turnout emerges with nontrivial
voting costs and modest altruism. The model can explain higher turnout
in close elections as well as votes for third-party candidates with no
prospect of victory. For certain parameters, these third party
candidates lose votes to more popular candidates, a phenomenon often
called strategic voting. For other parameters, the model predicts
"vote-stealing" where the addition of a third candidate robs a viable
major candidate of electoral support.
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