Political ads by presidential candidates are now flooding the airwaves in Wisconsin.
VIDEO: Watch The Report
A WISC-TV Reality Check found that the negative ads just might be better for voters' decision-making than they might think.
Sen. Hillary Clinton has been focusing ads on her proposed policies and her record. Sen. Barack Obama has been airing ads that introduce him to voters and show them his vision.
But the tactics are changing. Clinton has begun running an ad that is the first negative ad of the entire Democratic presidential campaign. It focuses on how she's accepted an initiation to participate in a debate in Wisconsin, and Obama hasn't.
One University of Wisconsin-Madison professor said he believes negative ads can be a good thing for voters.
"Negative advertising is more likely to be factually correct than positive advertising, and is also more likely to be on issues than positive ads," said Ken Goldstein, who heads up the University of Wisconsin Advertising Project.
Goldstein said that not only are negative ads more likely to be correct or on issues, but they also point out contrast between candidates, or get voters to go out and look for more information. Goldstein's research shows than in 2004, positive ads had around 43 percent policy content, while negative ads were nearly 60 percent policy-related.
"What shines through a fog of information is sometimes a negative message. It tells people, 'Hey, something important is going on here; we're electing a president, pay attention,'" Goldstein said. "And when voters pay attention, when they're a little anxious or even a little fearful, we know that they're much more open to learning."
But he pointed out that, while effective, negative ads aren't always the best option for the candidate. Obama is new to many voters, while Clinton is not. Goldstein said that Obama's ads don't need to define differences, they need to define himself.
In a conference call announcing the Clinton debate ad, her communications director said they didn't believe the ad was negative, saying that a "call to debate is a positive thing."
The Obama campaign is responding to the Clinton ad by airing its own ad starting Friday statewide. That ad says the two have debated 18 times and defends Obama's policy stances.
Note: Send ideas for Reality Check to firstname.lastname@example.org.