Colorado Democratic Sen. Mark Udall is offended by a new campaign ad aired by his opponent, Republican Rep. Cory Gardner, in which Gardner calls him a “very nice guy.”

Of course, Gardner goes on to say that despite his likeability, Udall “will never change the Senate” because of the deep roots his family has there.

“He is the Senate,” Gardner says.

He goes on to point out that two of Udall’s cousins are senators (Tom Udall from New Mexico and Mike Lee from Utah) and that Udall’s father, Morris “Mo” Udall, who was a respected longtime congressman, once ran for president.

Gardner then contrasts that with his own family history, gesturing to his father in the background, working on a tractor.

“My dad? Well, he sells tractors, just like my granddad,” Gardner says. “And I’m darned proud of that.”

Udall wasted no time calling the ad “low” and saying Gardner had crossed a line by bringing family into politics.

“This race should be about who can better represent the great state of Colorado, not personal attacks on our families,” he said in a statement that was first reported by the Denver Post. “So, to see Congressman Gardner decide to go after my late father and members of my family in a negative ad. That’s just low, no matter what ‘generation’ Congressman Gardner claims to represent. I’m proud of my dad. He was as Western and bipartisan and commonsense as a man could get.”

“Folks loved my dad, I loved my dad, and that isn’t going to change no matter how personal and negative Congressman Gardner’s campaign gets,” he continued.

“This just isn’t the way we do things here in Colorado, and it’s a shame Congressman Gardner doesn’t know any better.”

Gardner’s campaign fired back that Udall is too partisan to take a compliment.

“This is rich,” Gardner campaign manager Chris Hansen told the Post. “For six months Sen. Udall has done nothing but wage the nastiest campaign in America and now he is upset that we are calling him a nice guy? Mark Udall has been in Washington for so long and is so partisan that he can’t even take a compliment when it comes from the other party.”

As a sign of the bipartisan respect Mo Udall earned during his tenure, Arizona Sen. John McCain said recently that he wouldn’t campaign in Colorado on Gardner’s behalf because of his close ties to the Udall family.

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