District Complexity and the Personal Vote

Incumbents tend to win with higher margins in less ideologically constrained districts. I argue that incumbents are advantaged by this electoral landscape in part because they work harder to cultivate a personal vote. Utilizing data on earmarks, I find that despite winning with a larger margin of victory, these incumbents act much like their colleagues who narrowly escaped electoral defeat. By more accurately measuring perceptions of electoral vulnerability, we also see stronger evidence linking district marginality to distributive politics. Such incentives appear to stem not from the risks of position taking, but from the weaker party attachments among constituents.