District Size and Proximity to the Pork Barrel in Congressional Elections

We propose that district size moderates the relationship between pork barrel spending and U.S. House election outcomes. Our argument is two-fold: (1) pork has a greater effect on citizens' lives—and thus, their vote—when allocated in geographic proximity to them; and (2) in smaller districts, pork projects are proximate for more people, increasing their reach and impact. We provide empirical support for our argument using a pre-registered survey experiment and observational data from two recent Congresses. Most notably, we find that earmarks are modestly associated with higher vote shares for the incumbent in smaller districts but make no electoral difference in larger districts. These results cannot be explained by other legislator and district characteristics. Our paper highlights how the physical characteristics of House districts can shape electoral accountability and offers a novel structural explanation for why decades of research have found almost no overall relationship between pork and votes.