We utilize a novel experimental design to assess voter selectivity to political advertising. We randomly expose respondents to comparable positive or negative ads aired by Democratic or Republican candidates from the 2012 Presidential race and the 2013 Virginia Gubernatorial contest. The experiment closely mirrors real consumption of campaign information by allowing subjects to skip ads after five seconds, re-watch and share ads with friends. Using these measures of ad-seeking behavior, we find little evidence that negativity influences self-exposure to election advertising. We find partisans disproportionately tune out ads aired by their party’s opponents, though this behavior is asymmetric: Republican-identifiers are more consistent screeners of partisan ads than Democrats. The results advance our understanding of selectivity, showing that party source, and not ad tone, interacts with partisanship to mediate campaign exposure. The findings have important implications about the role self-exposure to information plays in campaigns and elections in a post-broadcast era.