Kansas Republican Sen. Pat Roberts blasted his independent opponent Greg Orman on Monday for not formally apologizing for a wisecrack that appeared to liken former Republican presidential nominee Bob Dole to a clown.

"The whole incident has just been an indication of how out of touch my opponent is," Roberts said on Fox News' "America's Newsroom." "He has insulted Bob Dole, who's an American icon and certainly a Kansas icon."

"I don't know how he can say something like that. You call Bob Dole a clown and then you have a lengthy statement that goes into a political diatribe. All he had to do is just apologize to Bob. The latest we hear indicated … that he didn't apologize to Bob Dole."

Dole and a number of high-profile Republican politicians have flown into Kansas recently to stump for the embattled incumbent Roberts. When asked about the surrogate surge on Friday, Orman said: "It sort of seems like a Washington establishment clown car to me," adding: "Every day a new person comes out of that car."

Dole told Fox News that he received a "lengthy apology" from Orman, but campaign officials said the email was rather an attempt to set the record straight after others "misconstrued" the remarks.

The email, obtained by Fox News, bears out that Orman indeed did not formally apologize to the former senator.

Roberts called the incident "absolutely outrageous" and something that will follow Orman "throughout his whole career."

"Regardless of politics, everybody is going to think, 'Well there's Greg Orman, here's the guy that insulted Bob Dole by calling him a clown,'" he said.

The retooled Roberts campaign spent October trimming Orman's double-digit lead down to one point in a contest that could determine which party controls the upper chamber.

"A vote for Greg Orman is a vote for Obama," Roberts said. "He is not an independent, he's a liberal Democrat."