Clinton, Obama Home In on Wisc.

Tomorrow's primary in Wisconsin won’t decide the Democratic nomination, but Barack Obama and Hillary Clinton are fighting tooth and nail anyway, Politico reports, airing their first negative ads of the campaign and taking shots at each other through aides. At stake is momentum: Obama doesn’t want to break his winning streak, and Clinton wants to prevent another Potomac-level blowout.

Obama supporters were particularly incensed by a Clinton mailer characterizing Obama’s health care plan as “unscrupulous demagoguery.” Obama supporter Ted Kennedy called the pamphlet “the kind of distortion we had back in 1994,” when Clinton was mounting her first health reform plan. Hawaii also holds a primary tomorrow; Obama is expected to dominate in the state where he grew up. (More Wisconsin primary stories.)