Liam C Malloy and Shanna Pearson-Merkowitz (2016). Going Positive: The Effects of Negative and Positive Advertising on Candidate Success and Voter Turnout. Research and Politics, January-March 2016.
This definitive new study includes TV ad spending in over 600 media markets in campaigns for president, governor and U.S. senate in 1996, 2000, 2002, 2004, and 2008, and definitively shows that attack ads do more harm than good.
According to the study, only positive messaging works, and only under certain conditions:
- In competitive areas – areas in which the candidate either won or lost by less than 10 points, neither positive nor negative ads had a significant impact on vote share, even when one candidate outspent the other. Even though results were small, the results clearly showed that running negative ads REDUCES your own vote share, regardless of whether your opponent’s ads were positive or negative.
- In non-competitive areas – running more ads than their opponent increased a candidate’s share of the vote, but only when those ads were positive. Running 10% more positive ads than your opponent gave you a 0.43% increase in vote share, while a 2 to 1 advantage in positive ads gave you a 2.8% increase in vote share. When running negative ads, running more ads than their opponent actually DECREASED their share of the vote.
- In all areas – the more positive ads you ran, the better your party’s turnout: the more negative ads you ran, the lower your party’s turnout.
“The only beneficial results from campaign advertising are generated from advertising a candidate’s strengths… there are no benefits from attacking one’s opponent, even if the opponent has decided to ‘go on the attack’.”
These findings are consistent with 30 years’ worth of previous research.
Given the depth of research on negative advertising in campaigns, scholars have wondered why candidates continue to attack their opponents. We build on this research by considering real-world campaign contexts in which candidates are working in competition with each other and have to react to the decisions of the opposing campaign.
Our results suggest that it is never efficacious for candidates to run attack ads, but running positive ads can increase a candidate’s margin of victory.
These results are conditioned by two factors: candidates must both stay positive and out-advertise their opponent. Second, the effects of positive advertising are strongest in areas where the candidate is losing or winning by a large margin—areas where they might be tempted to not advertise at all.