Public and scholarly attention on fundraising events often focuses on concerns around selective responsiveness to donors, particularly when those donors may have preferences that are unrepresentative of the broader constituency. These accounts have primarily relied on anecdotal evidence, due largely to a lack of systematic data on event fundraising attendance. We use data from U.S. state-level campaign finance disclosures -- which reveal whether or not a donation was made for attending a fundraising event -- alongside voter files merged to consumer data (L2 Data), as well as national-level surveys to explore consequences of event fundraising for responsiveness. We first examine the representativeness of event donors along lines of income and demographics, compared both to non-event donors and registered voters. Moreover, we analyze the degree of issue alignment between politicians and each comparison group. Furthermore, we examine how exposure to event donors moderates legislators' responsiveness to district preferences. We also analyze the relationship between event-donor exposure and misperceptions of constituents' views. Our preliminary results indicate that event donors are richer, and more likely to be male and white than non-event donors, and that both groups of donors are richer, older, and more likely to be male and white than both the underlying constituency and the state as a whole. Moreover, on economically salient issues, event donors are more likely to be aligned with their member of Congress than non-donors.