Outside of the Old Boys Club? Gender Differences in Outside Groups' Advertising Support for US Senate Candidates

Since 2010, televised campaign ads have proliferated, raising questions about gender differences in the number of ads outside groups air. Assuming incumbent Democratic women and Democratic women with prior office-holding experience run with support from their party and interest groups, we expect Democratic-leaning groups air more favorable ads supporting Democrats in races that include experienced or incumbent Democratic women than they do in races that include experienced or incumbent Democratic men. Conversely, we assume Republican women receive less support from their party and interest groups. We expect outside groups air more favorable ads supporting Republicans in races featuring experienced or incumbent Republican men than races including experienced or incumbent Republican women. Given the potential for backlash to attack ads, we expect Democratic- and Republican-leaning groups air more ads in races including experienced or incumbent male opponents than in races that include experienced or incumbent female opponents. We test these hypotheses by focusing on 2010-2018 U.S. Senate races and combining original data with data from the Wesleyan Media Project, the U.S. Census, and the Cook Political Report. Democratic- and Republican-leaning groups both sponsor significantly fewer ads in races featuring experienced female Democratic candidates compared to races including experienced male Democratic candidates.