How Clinton's Exit May Boost Obama

The study found that if two options vie for a consumer's or voter's preference, and a third option enters and leaves the market, the remaining option most similar to the exiting one benefits. The similar features get more attention, and consumers think, "Oh, that must be important," the researchers say.

"This is exactly what happened in the Democratic primaries this year," said researcher Akshay Rao of the University of Minnesota's Carlson School of Management. "We have Obama and Clinton going at it for months after the Republican primary has been decided. John McCain couldn't buy media attention at that time because everybody is focused on the attributes that Obama and Clinton were arguing about."

He added that by withdrawing after the primaries, Clinton left in her wake an impression that the shared Obama-Clinton attributes and issue stances were important. With Clinton out of the picture, Obama could take all of that popular appeal. 

Rao and his colleagues tested this phenomenon by having groups of undergraduate students complete questionnaires in which they had to choose between three options, one of which subsequently became unavailable.

These sets of options included unnamed political candidates, beer, healthcare plans, cars and cruise lines.

In one scenario, participants were asked to respond to a newspaper poll about unnamed presidential candidates who had been rated on economic and international policy. One candidate performed well on economic policy, the other on international policy, and the third candidate either dominated the other two on both attributes or outperformed the so-called target candidate on one type of policy.

When the third candidate stayed in this virtual race, 72 percent of the participants chose that person, while nobody chose the target candidate. When the third option dropped out, more than 50 percent of those who originally selected that third option chose the target. None of the participants who had chosen the rival were swayed toward the target.

Asked if staunch "Hillary supporters" would sway toward Obama, Rao said his results can't answer that question. But the findings do speak to swing voters, which make up about 20 percent of U.S. voters, according to recent Gallup poll estimates.

"The presence or absence of the third option influences people whose attribute preferences are labile — they don't know which attribute is important," Rao told LiveScience. "Is energy policy more important than foreign policy? … The fact that you've got two candidates talking ad nauseam about energy policy makes them turn their heads and say that must be important."

The results will be published in a forthcoming issue of the Journal of Marketing Research.

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