In a model that relies entirely on legal and structural factors, Wright (1989) seeks to account for changes in voter participation from the initial primary to the runoff. This article tests an alternative, campaign–centered model of voter turnout in 109 congressional runoffs from 1982 through 1996. The analysis indicates that candidate–centered factors, including the amount of money expended by the candidates in the runoff and the political experience of the primary leader, influence turnout in runoff primaries. Generally, when more money is spent during the runoff, voter participation declines less relative to the initial primary, suggesting that a more stimulated political environment encourages greater participation. Spending before the initial primary is less influential than spending between the primary and runoff in maintaining voter turnout, which indicates that any potential effects from stimulation of the environment in the prior campaign have largely dissipated by the time of the second election.