It is a common observation that many individuals vote despite the fact that, in
elections with even a moderate number of voters, the probability their vote will be
pivotal is quite small. The theoretical solution of positing that individuals receive
utility from the act of voting itself \explains" why individuals vote, but it leaves
open the question of whether or not there is a signi cant margin of individuals
who consider the e ect of their vote on the outcome in deciding whether or not
I develop a rational choice model of voting in union representation elections
(government supervised secret ballot elections, generally held at the workplace,
on the question of whether the workers would like to be represented by a union).
These elections provide a particularly good laboratory to study voter behavior
because many of the elections have su ciently few eligible voters that individuals
can have a substantial probability of being pivotal. I implement this model
empirically using data on over 75,000 of these elections held from 1972-2009.
The results suggest that most individuals (over 80 percent) vote in these elec-
tions independent of consideration of the likelihood that they will be pivotal.
Among the remainder, it appears that 1) the likelihood of voting falls with elec-
tion size, 2) the likelihood of voting increases with the expected closeness of the
election outcome, and 3) the marginal e ect of closeness on the likelihood of
voting increases in magnitude with election size. While the rst two ndings are
consistent with the standard rational choice model, the third is not. The results
suggest that, while these individuals consider rst-order variation in the proba-
bility that they will be pivotal, they do not carry out a complete calculation of
the probability of being pivotal.