The presumed Scott Brown-Elizabeth Warren matchup for Senate in Massachusetts is off to a very serious issues-related start, with each one joking about the other's history (or lack thereof) of posing naked in magazines.

The first shot was fired a couple of nights ago at a Democratic candidates debate, where Warren referenced Scott Brown's history of showing bush in Cosmo back in the '80s:

Brown paid for law school, in part, by posing nude for Cosmopolitan magazine, the candidates were told. How did they?

"I kept my clothes on," Warren said, again to laughter, before outlining her true blend of loans and work-study.

And then on the radio this morning, Scott Brown retaliated by being all like, Good, because she's nasty lookin' and who wants to see that right?

INTERVIEWER: Have you officially responded to Elizabeth Warren's comment about how she didn't take her clothes off?

SCOTT BROWN: [LAUGHTER] Thank God.

Oh man. The only way to decide this election is with a naked mud fight, next to Ted Kennedy's grave.

[Images via AP]