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If Minnesotans are half as nice as stereotype dictates, they can't be much pleased with the ongoing Senate contest between incumbent Republican Norm Coleman and his main Democratic challenger, Al Franken. Both candidates' advertising got so acrimonious last week that Franken released a spot defending himself against an earlier Coleman ad that bashed him for "tasteless, sexist jokes and writing all that juicy porn."

"Look, I'm not proud of every joke I've ever told," Franken admits in his newest spot (subscription), released Thursday night. "But I know there's a difference between what you say as a comedian and what you do as a U.S. senator." He then pivots to Coleman's record as senator, criticizing him for supporting President Bush on the Iraq war and for taking "millions from big oil and special interests." (The Center for Responsive Politics, a group that tracks campaign donations, reports that Coleman has received some $3.1 million from political action committees.)

Franken was responding to an ad (subscription) released earlier in the week by the Coleman campaign in which a jovial everyman character and his bowling buddies remind viewers of the laundry list of mini-scandals that have plagued the former comedian's candidacy. The litany includes Franken's failure to pay taxes fully in some states, off-color jokes he made before entering politics and articles written for Playboy in 2000.

"Norm Coleman put up a fairly ridiculous attack ad," said Andy Barr, a Franken campaign spokesman. "Al wanted to address it head on and then move on to what this race is really about." For its part, the Coleman campaign, which had not responded to requests for comment as of press time, released a statement accusing Franken of "trying to apologize for a 30-year record of this type of humor."

It didn't take long for the attack ads to reach this level of intensity, usually reserved for the later stages of campaigning. The first negative buy from either candidate appeared just one week ago (outside groups have already paid for pot-spots against both Franken and Coleman) when Franken aired an ad (subscription) charging Coleman with rubber-stamping Bush's policies and accepting money from special interests -- largely the same themes he's currently pressing in his latest, more defensive ad buy.