Specifying the Impact of Incumbency On State Legislative Elections

Abstract

Prior research, based on the analysis of aggregate-level state legislative election data, has documented a decline in the marginality of state legislative districts. Over the past twenty or so years, state legislators, much like congressional incumbents, have been winning reelection by larger margins of the vote. By taking advantage of district-level, state legislative election data, the research presented here specifies the relative impact of incumbency on district marginality, while controlling for statewide party trends. More specifically, it follows the lead of congressional elections studies, examining the impact of retirement slump and sophomore surge on the legislative district vote. In general, the legislative district vote reflects both a retirement slump and a sophomore surge, with the magnitude of their impact being conditioned by the level of contested incumbent victories in a state.