Updated

The Senate race in Massachusetts is going for the civility vote as Republican Sen. Scott Brown and Democratic challenger Elizabeth Warren have agreed --- under threat of financial penalty to themselves -- to ban third party ads from their race.

Brown told Fox News on Monday that he and Warren have signed off on a "document, legal and binding," agreeing to get the outside ads out -- with the kicker that they donate to charity half the price of ads that are run in their name in the state.

"By having 50 percent of that negative or positive ad buy go to charity of the other person's choice, it's an incentive to keep those groups out," Brown said, calling it the first deal of its kind in the country.

"It has real teeth too," he said.

Warren, who was President Obama's pick to head up the Consumer Financial Protection Bureau, her brainchild, and is considered by some as the mother of the Occupy Wall Street movement, sent Brown the signed agreement on Monday morning.

Calling it "an historic agreement," Warren spokeswoman Alethea Harney said the two will try to enforce the deal by sending letters to television stations and third parties asking them to desist from placing ads.

Warren "wants to work on this campaign based on her ideas and her values, and work on what she believes," she said.

"We have the opportunity to set an example for the rest of the country. Let's do it," Warren wrote in a letter to Brown earlier this month.

Brown said he wants to ban the ads so the people of Massachusetts can decide for themselves about the candidates.

"They're false and misleading. People know better. They're smarter. ... They want to know how a particular candidate is going to draw distinctions and get their vote, earn their vote. They don't need these outside groups trying to buy elections and do things inappropriately," he said.

Even without outside ads, Massachusetts voters shouldn't think they'll be free of political bombardments. Both candidates have raised serious money for the campaign.

Warren's campaign reported raising $5.7 million in the fourth quarter -- on top of $3.15 million raised in the third quarter, with more than $6 million cash on hand.

Brown's third quarter financing, the latest report available, showed $5.3 million raised and $10.5 million cash on hand.