MINNEAPOLIS (WCCO) – Former Minnesota Gov. Arne Carlson, a Republican, has endorsed Richard Painter as he runs as a Democrat for the U.S. Senate seat left vacant by Al Franken.

Painter’s campaign celebrated the cross-over endorsement Monday, saying that it showed the 56-year-old’s strength as a candidate in the general election.

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(credit: CBS)

In a statement, Carlson praised Painter, a prominent critic of President Donald Trump on the cable news circuit, as a “one of the most refreshing voices of intelligence and straight talk to come upon the Minnesota scene in decades.”

“I am excited about his candidacy,” he added.

Painter, a former ethics lawyer for President George W. Bush, announced last month that he’d be running for the U.S. Senate seat left open by Franken’s departure in the wake of a torrent of sexual misconduct allegations.

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While Painter has been a lifelong Republican, he said he would run as a Democrat against incumbent Sen. Tina Smith (a Democrat) and Republican challenger, state Sen. Karin Housley.

“The Republican Party has really gone way off the deep end, very far away from the values of the Republican Party of Gov. Arne Carlson and other moderates,” Painter said on WCCO Sunday Morning. “And now, with backing President Trump, it is unacceptable for our Democracy, what is happening to our country.”

In a recent blog post, Carlson noted that all three candidates for the Senate seat have a problem with name recognition, which could pose a particularly big obstacle for Smith.

“But the bottom line is simple,” the former governor wrote. “That Senate seat is up for grabs.”

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Although Smith is the incumbent, this will be her first election, as she was appointed to the Senate by Gov. Mark Dayton. Prior to serving in Washington, she was Dayton’s lieutenant governor.