In a tense, final confrontation less than 36 hours before the polls open, Minnesota's U.S. Senate candidates blasted one another Sunday over allegations and countercharges that have threatened to consume the contest in its closing week.

Debate moderator Gary Eichten, of Minnesota Public Radio, went right to the heart of the controversy in the opening moments of the debate, asking Sen. Norm Coleman point blank: "For the record, have you or your family received any money or gifts from friends, associates or supporters that you haven't reported to the U.S. Senate?"

"The answer to that is just no, Gary," Coleman said flatly, but then immediately laid into Democratic challenger Al Franken for refusing to denounce Democratic Party ads recounting allegations that a top contributor sought to funnel $75,000 to Coleman. "My anger is over an ad defaming my wife," Coleman said, adding, "There's a line in this business you don't cross."

Franken countered that he had no connection to the allegations and said: "This is not about me. ... This is about Sen. Coleman's political sugar daddy."

Independence Party candidate Dean Barkley responded to the lengthy exchange by saying: "I think now you know one of the reasons I'm running."

The final, hourlong debate at the Fitzgerald Theater in St. Paul reflected the elbows-out, rough-edged nature of a Senate race that has been the longest, costliest and most brutally fought in state history. Despite admonitions to remain quiet, audience members cheered, booed, hissed and even catcalled as the debate unfolded.

Sunday's punishing round of blows was triggered by a fracas that began last week, in which a top Coleman donor was accused in a lawsuit of having steered money Coleman's way through a company in Texas.

The donor, Minneapolis businessman Nasser Kazeminy, is being sued for allegedly having directed the Texas company to send $75,000 to a Minneapolis insurance firm that employs Coleman's wife, Laurie, as an independent contractor. The suit alleges that Kazeminy told executives at the Houston firm that he wanted to aid the Colemans financially.

In the debate, Coleman repeatedly claimed that attacks on his wife crossed the line,and used the theme to revisit controversial writings and comedy ideas from Franken's earlier career that Republicans have relentlessly assailed.

"Al, maybe you just don't know that there are lines you don't cross," Coleman said to Franken at one point. "Maybe that's your career. Jokes about rape ... pornography."

Franken responded: "Norm Coleman can't blame this on me. ... This is Norm Coleman's problem. This is Nasser Kazeminy's problem. But the culture of political corruption is all of our problem. ... I am saying the charges in this are very serious."

Plopped between the two combatants at a small table center stage, Barkley said: "I don't know who's right or wrong." The timing of the charges, he said, seemed suspect. But Barkley added, smiling: "I better be careful what I say or I might end up getting sued, too."

Familiar themes

When the debate moved on to other matters, the candidates returned to familiar themes, with Coleman touting his ability to get things done, Franken pledging to refocus Washington's attention on the middle class, and Barkley recommending strong medicine and plain talk to deal with a mounting federal deficit and debt.

"The middle class is angry," Barkley said. "I'm angry; that's why I'm running." He pushed an ethics reform agenda that would block members of Congress from taking contributions from industries their committees regulate. "At least let's take the direct bribery out of politics," he said, to audience cheers.

"If we simply tear the institutions apart, we can't solve problems," Coleman said. "We have real work to do, and if you just play to the partisan divide and the anger, you accomplish nothing."

Franken listed a number of programs he supports, including a $5,000 tuition tax credit, which he said promise "a return on investment."

"We have to grow our way out of this," he said, referring to the nation's financial crisis.

Barkley replied: "If you're looking for somebody to make promises that can't be kept, I'm not your guy."

Franken proposed a lifetime ban on lobbying by former members of Congress to reduce the power of special interests. Coleman said he opposed it because it presumes dishonesty among politicians. Barkley, who has worked as a lobbyist, did not address the question.

$40 million brawl

The debate was the last face-to-face encounter among the contenders in a nearly two-year, $40-million-plus race that has been among the most vicious in the country, featuring harsh ads and an edge that betrays the anxiety felt by Republicans as they attempt to prevent Democrats from taking a filibuster-proof majority in the U.S. Senate.

Earlier Sunday, GOP chairman Ron Carey accused the Star Tribune of receiving information about the allegations in the lawsuit before it was even filed, then "ambushing" Coleman in St. Cloud last week to question him about it. Using footage taken during that encounter by a DFL Party tracker, the Democratic Senate Campaign Committee has aired a series of anti-Coleman ads.

"These two reporters in the film that's being used by the DSCC against Senator Norm Coleman deserve an Oscar nomination for their role of ... chasing this senator to St. Cloud, and then knowing that the camera's rolling for the Democrats, yelling out these accusations or these questions accusing him of wrongdoing, or certainly implying wrongdoing," Carey said.

In response, Star Tribune Editor Nancy Barnes said Sunday that "we stand by our reporting on the story." An editor's note has been posted on the Star Tribune's "Politically Connected" website since early Saturday that says:

"The Democratic Senate Campaign Committee is running TV ads featuring a Star Tribune reporter questioning Sen. Norm Coleman about a lawsuit noted in this report. The video in the ad was filmed without the knowledge or consent of the Star Tribune."

Heading into Sunday's debate, Franken held a slim lead over Coleman in the latest Star Tribune Minnesota Poll, while some other polls showed a narrow Coleman lead. Barkley is running a distant third.

A flurry of last-minute campaigning is expected on all sides, with heavyweights Rudy Guiliani and Hillary Rodham Clinton coming to the state today to campaign.

Staff writer Aimée Blanchette contributed to this report.

Patricia Lopez • 651-222-1288