How do political debates affect advertising?

"This enduring popularity generates an intense competition for the commercial slots that follow broadcast debates," write authors Alison Jing Xu (University of Toronto) and Robert S. Wyer Jr. (The Chinese University of Hong Kong). "The fact that these commercials are widely viewed, however, does not guarantee their effectiveness."

The authors studied (and manipulated) the mindsets of participants who were exposed to various types of persuasive communications. "We proposed and found that inducing participants to make supportive elaborations on a series of propositions activated a bolstering mindset that increased the effectiveness of an unrelated, subsequent ad," the authors write. But the authors found that participants who activated a counterarguing mindset were less persuaded by the same ads.

In one experiment, the authors found that consumers in a bolstering mindset (people who generated thoughts about positions they already agreed with) were more likely to be persuaded by a vacation spot ad than their counterparts who were in the counterarguing mindset, which increased the number of negative thoughts toward the vacation spot.

In another study, the authors tested participants who self-categorized as Republicans, Democrats, or independents by assigning them to one of four conditions. Some watched Barack Obama's speech on his economic plan. Others watched a speech by John McCain, a debate between the two candidates, or nothing at all. "Participants with a strong a priori preference for either candidate were motivated to bolster their preferred candidate's speech," the authors write. "In all cases, developing a bolstering mindset increased participants' evaluations of the brands promoted in the commercial. However, acquiring a counterarguing mindset decreased participants' evaluations of that brand."

"Even though the quality of an ad plays an important role in determining its impact, the context in which is appears can sometimes decrease its effectiveness," the authors conclude.