As every election day approaches, voters all across the country are forced to endure “saturation bombing” in the form of political advertisements from every manner of candidate and cause. During the 1996 campaign, for instance, the major presidential candidates aired 5,700 advertisements in the Los Angeles media market. Campaign advertising is now such a strong force that political analysts habitually attribute electoral outcomes directly to some facet of the candidates' advertising tactics. In 1996, leading newspapers diagnosed the “winning” strategy of the Clinton campaign's ad team the day after the election.

It is hardly surprising, of course, that the very political consultants who design the advertisements claim that these messages influence electoral outcomes. But more objective sources, including a substantial body of social science research, also support this conclusion. Whether one learns about it in the New York Times or the Public Opinion Quarterly, campaign advertising seems to matter.

Although there is an emerging consensus about the efficacy of advertising (see Goldstein 1997; Shaw 1997), little is known about the psychological mechanisms relating campaign advertisements to support for the sponsoring candidate. Most prior research has been preoccupied with refuting the “minimalist” conception of political campaigns (see Iyengar 1996). Higher-order questions concerning the specific attributes of persuasive advertisements or the reasoning process employed by voters remain unanswered. This essay takes a first step toward understanding the mechanism of persuasion by specifying and testing one particular psychological account of the “winning” message.

Given its wealth of evidence on attitude change in a variety of contexts, the literature of social psychology is the natural springboard for political advertising research.