BOB GARFIELD: Dubner’s is a minority opinion. The data speak differently to different researchers. University of Virginia political science professor Paul Freedman also believes that campaign ads don't change that many minds, but maybe they change just enough to make a difference. He’s the coauthor of Campaign Advertising and American Democracy, and he had long observed that political advertising was the whipping boy of American politics, so maligned, so loathed, so powerful. So he and four colleagues set out in 1998 to gauge the real power of the ads by examining a decade’s worth of data. They looked at precisely where ads had been broadcast, in what races, to which audiences, and they cross-referenced that information with data from surveys asking how the ads affected the votes of viewers. What researchers found was that most voters are exposed to hundreds of TV ads during a campaign season. Voters in hotly contested districts could see thousands of ads. As to the impact of the advertising, well, what Freedman and his colleagues learned upends the conventional wisdom that campaign ads, especially negative ads, are so toxic that they actually suppress voter turnout.

PAUL FREEDMAN: What we found is that in fact election campaigns are a lot like fights on the schoolyard. Do kids run away and say, we don't want to participate? We feel depressed and alienated? No. People run over to see the action, and they begin asking questions. What are they fighting about? Maybe there’s reason to expect that election campaigns are like schoolyard fights.

BOB GARFIELD: And in a nutshell, your conclusions?

PAUL FREEDMAN: When it comes to political information, most Americans are fairly ill informed. And what ads do is to really serve as nutritional supplements. They're jam-packed in some cases with relevant information about the candidates, about the race, about the issues, coated in an emotional, easy-to-swallow wrapping.

BOB GARFIELD: The vast majority of the attack ads I've seen take nominal facts about legislative votes or personal history and then they twist them into big lies. And I'm talking about Republicans and Democrats both. And the idea that these things motivate voters to me is terrifying.

PAUL FREEDMAN: [LAUGHS]

BOB GARFIELD: Nutritional supplements? Isn't it more like tar and nicotine?

PAUL FREEDMAN: Well, nutritional supplements in the sense that at the end of a campaign, voters who have seen more ads simply know more than voters who have seen fewer ads. Certainly some ads are misleading. I don't think anybody’s suggesting that advertising can be a substitute for a C-SPAN debate on a particular issue. We're not making policy scholars out of viewers because we [BOB LAUGHS] bombard them with a bunch of 30-second ads. But the more ads a voter has seen during the course of an election campaign, the more likely he or she is to care about the outcome of the race and the more likely they are to actually vote on Election Day.

BOB GARFIELD: Can you quantify this?

PAUL FREEDMAN: There are many different factors that combine to shape whether or not an individual’s going to turn out to vote on Election Day. Education is one of the most important factors. Partisanship and how strong an attachment to one of the political parties you feel, whether or not you’re contacted by a campaign, the more money you have, the more likely you are to vote. Television advertising has a relatively modest effect. We're talking about the margins. We're talking about increasing the probability of voter turnout by really less than 10 percentage points. Now, that’s not huge, but it’s not nothing. Many Senate races this cycle, and many House races, are going to be decided by very, very narrow margins. And so, changing voter turnout by two percentage points or three percentage points can make or break an election outcome.

BOB GARFIELD: Well, I guess you've talked me down from the ledge to some degree, but my takeaway from all of this is that whoever gets elected from either party, the only thing we're absolutely sure of is that he or she has just participated in a schoolyard fight.

PAUL FREEDMAN: [LAUGHS] We're not simply at the mercy of the messages that campaigns and candidates put out for us. There’s an important role for the media. There’s an important role for academia. There’s an important role for organizations like PolitiFact and FactCheck.org. There’s a need to hold these candidates’ feet to the fire, and that, I think, is an important part of the campaign advertising landscape.

BOB GARFIELD: So considering how marginal the effect is, what about another piece of conventional wisdom that says that he who has the most money and can purchase the most media tonnage is going to prevail?

PAUL FREEDMAN: One of Barack Obama’s real advantages in 2008 was that he had much, much, much more money than John McCain to spend on television ads, and indeed he did. He out-broadcast John McCain by a wide margin. But in the primaries, John McCain was out-advertised and outspent by Mitt Romney. And so, it’s certainly not always the case that he or she who has the most money wins, but all else equal, you don't want to lose an election by one vote with one extra dollar in your campaign coffer.

BOB GARFIELD: Paul, thank you very much.

PAUL FREEDMAN: Bob, it’s my pleasure.

BOB GARFIELD: Paul Freedman is an associate professor in the Department of Politics at the University of Virginia and coauthor of Campaign Advertising and American Democracy.

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