The Campaign Matters: A Field Quasi-Experiment of Negative TV Advertising and Election Outcomes

Abstract

Do campaigns matter? Do negative TV advertisements affect vote outcomes in elections? The scholarly conventional wisdom suggests that negative advertisements have a limited impact on election outcomes. In contrast, based in part on analyzing the incentives of candidates and campaign consultants, we theorize that negative campaign advertisements affect vote outcomes in elections. Theoretically, negative advertisements should matter, yet nearly all empirical work showing that they do not has been based data where causality has been difficult to assess. In concert with a statewide political campaign in Pennsylvania, we conducted a field quasi-experiment of TV campaign advertising. We find that negative campaign advertising leads to about a three percentage-point vote share increase for the ad-sponsoring candidate in treated geographic areas when compared to those geographic areas where no ad was run.

Keywords: political behavior, electoral institutions, negative advertising, campaigns, elections, judicial politics, judicial elections, state politics, field experiment, quasi-experiment