Explaining major and third party candidate entry in U.S. gubernatorial elections, 1980-2005

While much scholarly research has focused on the quality of candidates in U.S. elections, the quantity of candidate participation has received much less attention. Consequently, there is little systematic evidence on what factors stimulate or dampen candidate entry into electoral contests, especially at the state level. In this article, we examine the effects of electoral laws, states' social and political climates, and incumbency on gubernatorial candidacies. We test our claims using an event-count model with the number of candidates contesting each gubernatorial election from 1980 to 2005 as the outcome of interest. We divide total candidate participation into major and third party candidates to observe whether the factors affect neither, one, or both types of candidacies. We find that electoral laws and incumbency play an important role in determining the number of candidacies in these elections, but the effect of these factors varies for the two types of candidates.