The Variable Incumbency Advantage: New Voters, Redistricting, and the Personal Vote

In this article we explore the personal vote costs of redistricting. After redistricting, incumbents often face significant numbers of new voters—voters that were previously in a different incumbent's district. Existing conceptualizations of the incumbency advantage suggest that the cost to incumbents of having new voters should be relatively small and predictable. We propose a different formulation: a variable incumbency advantage. We argue that any incumbency advantage among the electorate is a function of short-term effects, partisanship, and electoral saliency. We use a massive untapped dataset of neighborhood-level electoral data to test our model and to demonstrate how the intersection of the personal vote, redistricting, and short-term environmental variables can provide a healthy margin to incumbents—or end their careers.