An ad’s timing matters as much as its content. Spots criticizing an opponent tend to work differently early and late in campaigns. Before people have settled on a candidate, attack ads help them make up their minds. But these same ads depress turnout when seen later by voters who have already chosen which candidate to support.
4. A candidate should respond to an attack ad with a counterattack on the same issue.
In some cases, such a response may make sense; in others, it is precisely the wrong thing to do.
If an accusation cuts to the core of a candidate’s strength — say, the 2004 “swift boat” ad assault on John Kerry’s war service in Vietnam — then a strong rebuttal, preferably with evidence, might be warranted.
Often, however, these counterattacks pull candidates off their message. Research suggests that it’s better to spend ad dollars highlighting issues that play to a candidate’s strengths — such as those on which she has built a solid reputation or on which voters prefer her stance — rather than engaging an opponent on his issues.
Romney, for example, should probably not devote many ads to the fight against terrorism, an issue on which Obama fares relatively well in polling, or to the environment, a subject where Democrats have a reputational advantage.
Similarly, airing ads denying that you are a witch, as Christine O’Donnell did in her failed 2010 Senate bid, feeds a campaign theme that is unlikely to improve your odds on Election Day.
5. News organizations neutralize misleading ads by fact-checking them.
Such news stories may be well-intentioned, but there is no clear evidence that they reliably undercut misleading claims or manipulative tactics. Part of this may be because of volume; ads are repeated and reach many people who don’t watch, listen to or read the news.
Voter psychology also plays a role. While some news stories may weaken an ad’s effectiveness, many media reports end up extending the reach of the misleading statements they are trying to debunk: People hear the claim and remember it better than the journalist’s correction.
In 1992, CNN ran “ad watch” segments pointing out that Bill Clinton’s attacks on President George H.W. Bush’s handling of the economy were misleading and that Bush’s attacks on Clinton for raising taxes as governor were hypocritical. In both cases, viewers came away with more favorable views of the candidate whose ad was being criticized.
This tendency is exacerbated by the audience’s strong partisan convictions. Research shows that partisans tend to persist in believing inaccurate information, even after it is corrected, when that information makes their party look better or makes the other party look worse.
Ted Brader, the author of “Campaigning for Hearts and Minds: How Emotional Appeals in Political Ads Work,” is a professor of political science at the University of Michigan.
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