Small Campaign Donors

In this paper, we study the characteristics and behavior of small donors, and compare them to those of large donors. We first build a novel dataset including all the 340 million individual contributions reported to the U.S. Federal Election Commission between 2005 and 2020. Due to the particular legal structure of the new online fundraising platforms first used by Democrats (ActBlue) and now Republicans (WinRed), we are able to extract contribution-level information about a majority of the small donations. This allows us to identify “small" donors, i.e. donors who give less than $200 during a two-year electoral cycle to each committee, and to differentiate them from “large" donors. The analysis of this novel dataset delivers several new insights. First, we provide evidence on the growing number of small donors in the U.S. and on the magnitude of their contributions. Second, we find that small donors include more women and more ethnic minorities than large donors—with minorities still under-represented—while they do not differ much in terms of their geographical distribution. Third, using a saturated fixed effects model to explore the determinants of contributions by small and large donors, we find that the closeness of a race,whether the candidate and the donor live in the same district or state, and, to a lesser extent, the ethnic alignment between the donor and the candidate have a positive impact on contributions. We also find that donors contribute more to more extreme candidates. These effects are lower for small donors. Finally, we show that campaign TV ads affect the number and the size of contributions, and more so for small donors.