President Barack Obama and former Massachusettts Gov. Mitt Romney are the Tweedledee and Tweedledum of American foreign policy as the final televised debate of the 2012 presidential campaign proved. In Lewis Carroll’s Through The Looking Glass, the two twins gird themselves to fight each other over a broken rattle, but then back down. In the third debate, Obama and Romney mimicked the Looking Glass twins by largely backing away from real confrontation. With very slight differences in emphasis, the two agreed that Iran can’t have a nuclear bomb; Israel is a great friend; American troops will withdraw from Afghanistan by 2014; Pakistan and Syria are a mess; economic growth at home will make America strong abroad; and China should “play by the rules.” The chief difference is that Romney wants a bigger military than does Obama. So who “won” the debate? 

According to CNN, its CNN/ORC International poll of debate viewers found that 48 percent favored Obama compared to 40 percent for Romney, a result considered statistically even under the margin of error of plus-or-minus 4.5 percent. A poll of debate watchers in swing states by the Democratic shop Public Policy Polling found that 53 percent thought Obama was the winner of the third debate compared to 42 percent who picked Romney. As we all suffer through our post-debate let-downs, it's worth asking whether the debates give us any indication about who will win in November. Let’s see what the academic literature has to say.

A 2003 meta-analysis of 33 empirical studies of the effects of presidential debates published in the journal Communication Monographs found that such debates had only a modest impact on viewers, slightly increasing their knowledge of the issues under consideration, how the candidates' views matched up with their own, what issues were at stake, what the candidates' characters were like, and what their own vote preferences were. However, watching television debates had no effect on what viewers thought of a candidate’s competence. One significant finding from the analysis is that “the first general debate has a larger effect on vote preference than subsequent debates.” Since Romney pulled even with Obama in polling after he “won” the first debate, this suggests that the third debate will have no significant effect on voters’ preferences between now and the election.

In one corner you have the body language school of analysis which argues that viewers react more favorably to the candidate whose gestures and physical movements suggest dominance. Van Jones, former Obama administration green jobs czar, offered a crude version of this approach on CNN’s The Situation Room. “You had two guys up there—one was kind of acting like a douche, and one was acting kind of like a wimp,” declared Jones. He added, “Between a wimp and a douche, I think people are going to want somebody who seems like a stronger leader even if they were a little bit obnoxious.” (Jones later apologized for his word choice.)

Some academicians have more decorously expressed a similar view. According to LiveScience, after the first debate, Karen Studd, a nonverbal communications expert from George Mason University, observed that “Romney made vertical, predominantly up-to-down eye movements, a style that could be seen as connected to a top-down, authoritative approach.” On the other hand, she noted that Obama had “a more inclusive focus, preferring to take in the whole rather than a single piece of it, and he occupies space horizontally.” Even finger gestures matter to such analysts. During debates, Obama makes use of the so-called precision grip gesture (thumb to tip of fore-finger) that suggests to viewers that he is making a sharp sure point.  

Over at Psychology Today, Yale University psychologist Marianne LaFrance chimed in claiming that Romney had deployed “visual dominance” when debating Obama, e.g., when Romney spoke he looked at Obama and then looked away when Obama spoke. Implied message: “Listen up. I’m talking!” In addition, Romney maintained an “asymmetrical smile” throughout the debate, suggesting self-assurance. At lot of post-debate commentary concluded that Romney’s more aggressive debate performance helped him win favor among viewers. In fact, several polls found that after the first debate Romney’s favorability rating has moved past that of Obama.

Most studies find that televised presidential debates largely reinforce the partisan beliefs of watchers, not sway the minds of wavering voters. However, two Canadian social science researchers, Andre Blais from the University of Montreal and Andrea Perrella from the Wilfrid Laurier University, have uncovered some stable patterns in how voters react to televised presidential debates. In their 2008 article, “Systemic Effects of Televised Candidates’ Debates,” in The International Journal of Press/Politics, the two analyzed all U.S. presidential debates since 1976 and all Canadian party leader debates since 1988.

Blais and Perrella specifically wanted to know the following: (1) do debates affect overall voter evaluations of candidates; (2) are debates win/lose propositions; (3) do debates hurt incumbents; and (4) do debates help less popular candidates? The researchers devised a “thermometer” score in which voters signify their feelings about a candidate on a 0-to-100 scale. The voters’ “temperature” was taken five days before and five days after each debate.

To summarize, Blais and Perrella found that debates tend to improve voter evaluation of both candidates. In fact, after the first 2012 debate, according to the Gallup Poll the favorability ratings of both Obama and Romney ticked up slightly. The authors are a bit surprised by this result but speculate that voters positively evaluate both candidates based on their perception that they are competent defenders of their views. In addition, debates are not zero-sum events, since the researchers found that a candidate’s gain do not directly correspond to the amount of an opponent’s loss; both generally improved their images among voters. In their data, the researchers found that incumbents tend to lose “thermometer” popularity points before debates, but found that debates more often than not “nullify whatever negative impact incumbency might entail.” And finally the gap between front-runners and challengers narrows after televised debates. This appears to be the case because the less well-known challengers gain more from the debates.

Researchers have also looked into the effect of media spin on viewers of presidential campaign debates. A 2009 study in the Southern Communication Journal looked at how the post-debate coverage of CNN and Fox News affected voters’ perceptions of who won the first presidential debate between George W. Bush and John Kerry in 2004. Just after the debate, 25 percent of CNN viewers believed that Bush had won and 58 percent thought Kerry had. After listening to CNN commentators that changed to 20 percent for Bush to 62 percent for Kerry. Over at Fox, initially 24 percent thought Bush had won and 54 percent that Kerry had. The post-commentary shift among Fox viewers was much bigger, with 43 percent now claiming that Bush had won and 39 percent that Kerry had. Evidently, Fox News commentators can be especially persuasive.

Academicians have also looked into how the appearance of candidates affects the views of voters. A 2010 study in Political Psychology, for example, reported on subjects who looked at the faces of candidates for actual Senate and House of Representative races in 2004. The researchers found the candidates who were judged “as more likely to physically threaten” subjects had actually lost elections 65 percent of the time. The same study also found that “attractiveness was correlated with losing elections, with the effect being driven by faces of candidates who looked politically incompetent yet personally attractive.”

Finally, there is the old stand-by claim that the taller candidate tends to win. A 2012 study in The Leadership Quarterly by Dutch political scientists reported, “Using data on all presidential elections, we show that height is indeed an important factor in the US presidential elections. Candidates that were taller than their opponents received more popular votes, although they were not significantly more likely to win the actual election.” For the record, Barack Obama is 6 feet and one inch tall, and Mitt Romney stands at 6 feet and two inches.*

Given the boost that the first debate gave Romney, the general political science conclusion that debates have almost no effect on elections may turn out to be falsified. Whatever the result on November 6, it is undoubtedly the case that one of the chief functions of the presidential debates is to provide entertainment for the chattering classes.

*Disclosure: I am six feet and five inches tall, but I promise never to run for president of the United States.