Existing research offers competing predictions as to whether election outcomes affect the future political behavior of individual supporters. Drawing on a dataset of millions of donors across thousands of candidates in different races, this study analyzes a series of regression discontinuities to estimate the effect of donating to a barely winning candidate as opposed to a barely losing one. It finds that winning donors were substantially more likely to donate in the future to that same office type. These effects are large and occur even when their original candidate was not up for re-election. The results show that the consequences of election outcomes extend beyond control of a particular seat, and affect the future behavior of ordinary citizens.