Brown, Warren finally agree to debate schedule for Massachusetts Senate race

Sen. Scott Brown on Friday morning agreed to a fourth and final televised debate with Democratic challenger Elizabeth Warren after refusing previous invitations because of venues with ties to the Kennedy family.

"Scott Brown accepts the Boston Herald/UMASS Lowell debate invitation, concluding the debate schedule for the 2012 campaign," Brown campaign manager Jim Barnett announced in a statement. The decision is significant because it appears to end public bickering between the candidates over a mutually-agreed upon venue and host.

Brown previously refused an invitation to a debate sponsored by the University of Massachusetts at Boston and the Edward M. Kennedy Institute because Kennedy's widow, Victoria Reggie Kennedy, president of the Kennedy Institute board of trustees, would not abstain from taking sides in the Senate race.

Warren then remained mum on two radio debate invitations accepted by Brown while awaiting the Republican's decision on televised venues.

The debate, which will be the fourth televised debate of the general election campaign, will take place Sept. 27 and will be moderated by David Gregory of NBC's "Meet the Press."

The Massachusetts U.S. Senate campaign, which is one of the most hotly contested Senate races of the year, has been marked by sharp personal attacks over Warren's Native American heritage and Brown's Wall Street ties. But unlike most highly contested races playing out this year, outside groups have not played a role in pressing these lines of attack. In an unusual move, both candidates agreed in January to impose penalties on one another if outside groups run ads on their behalf or against their opponent.

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The outside ad ban has relegated attacks to campaign appearances by the candidates and to communications by their staff, further raising the stakes of debates and making them even more likely to include fireworks.