Mark Dayton's turbulent political career reached another high Wednesday as DFL leaders converged on the State Capitol to embrace a candidate who shunned their party's endorsement and won over primary voters instead. Before Democrats could even join Dayton to show their unity, Republicans signaled the start of a bloody campaign season as they attacked what they called Dayton's "erratic" behavior as a U.S. senator.

Dayton dismissed the attacks as predictable. "I expected the smears to start right away," he said. "Today is a unity afternoon for us." In a close, hard-fought race, Dayton had managed to score a victory over DFL-endorsed candidate Margaret Anderson Kelliher. DFL rival Matt Entenza ran a distant third.

Many of the A-list state Democrats, who days earlier had stumped for his competitors, praised Dayton at length Wednesday for what they called his lifelong commitment to core Democratic values such as improved education.

Hours after conceding the race, a puffy-eyed Kelliher stood before the crowd and said, "Today we unite as DFLers. We unite behind Mark Dayton and we unite to beat Tom Emmer. ... What matters now is putting a DFLer in the governor's office."

That effusive display of political harmony seemed in doubt on Election Night, when Kelliher and Dayton battled it out statewide, separated by a margin so thin a recount seemed in the offing.

Democrats awoke Wednesday morning to find Dayton had clawed his way to a comfortable 7,000-vote lead over Kelliher. Yet the Minnesota House Speaker refused to concede until nearly noon.

Dayton said he didn't feel any tension with the party, which backed Kelliher and had marshaled the bulk of her highly touted voter contact field operation.

"That was then and this is now," Dayton said. "I am just so grateful that everyone, starting with Speaker Kelliher and Rep. Entenza, is showing what truly amazing people they are."

Dayton also said he received congratulatory phone calls from President Obama and Vice President Biden.

Dayton now faces Republican challenger Emmer, who faced no major primary challenger, and Independence Party candidate Tom Horner, who crushed his primary opponents. Horner is a first-time candidate and Emmer has never run a statewide race. Dayton's last gubernatorial bid was in 1998, when he lost the primary.

Emmer made no public appearances Wednesday. His campaign said he was hunkered down to raise money for the general election contest against Dayton, a millionaire who so far has largely self-funded his campaign, and Horner, who has deep contacts in the business community.

Cullen Sheehan, Emmer's new campaign manager, made a point on Wednesday of congratulating Dayton and Horner.

"We look forward to vigorous debate in the weeks ahead," Sheehan said in a statement.

On the attack

By lunchtime, Republicans unveiled their first television ad of the campaign. It labeled Dayton "erratic" and questioned his judgment during a much-criticized decision to close his U.S. Senate office during what he believed to be a terrorist threat. The ad, which begins airing Thursday, notes that Time magazine named Dayton one of the nation's worst senators for his decision and that Dayton had given himself low grades for his single term.

Minnesota Republican Party Chairman Tony Sutton called Dayton's Senate record "a complete disaster," and said the risks were too great.

Dayton has long defended the decision to briefly close his Senate office as a prudent attempt to protect his staff and potential visitors, based on the top-level intelligence briefings given to senators at the time. He said he gave his Senate performance low marks because he has high expectations of himself. His single term in the Senate, he said, taught him he is better suited to the executive branch, where decisions can be made with more agility.

At the unity event, Dayton poked fun at his U.S. Senate tenure, saying Sen. Amy Klobuchar was a marked improvement over her predecessor -- himself.

It's unclear how the public will react to ads attacking Dayton. He has field-leading name recognition, is praised by many seniors for his championing of lower-cost prescription drugs and has powerful union backing.

"Sen. Dayton has personal issues and I think that he's dealt with them in a forthright manner," said Lou Frillman, a Democratic fundraiser. "You've got to admire that."

Baird Helgeson • 651-222-1288