Rick Santorum has suggested that Mitt Romney is not anti-gay enough.

During an appearance Sunday on ABC's This Week, Santorum laughed off claims by Romney that Santorum and Newt Gingrich “acted like Democrats.”

“Senator Santorum and Speaker Gingrich, they are the very Republicans who acted like Democrats, and when Republicans act like Democrats, they lose,” Romney said on Tuesday. “And in Newt Gingrich's case, he had to resign. In Rick Santorum's case, he lost by the biggest margin of any Senate incumbent since 1980.”

“Well, that's pretty funny for Mitt Romney saying I'm acting like a Democrat,” Santorum told host George Stephanopoulos. “You know, the question I get most often from the national media, are you too conservative to be elected president?”

“Why is it funny?” Stephanopoulos interrupted.

“Well, because, I mean, you know, Mitt Romney is the author of Romneycare, which is the biggest government expansion in the history of the state of Massachusetts and was the template for Obamacare. He's supported cap-and-trade and … He was for the Wall Street bailouts. He ran as to the left of Ted Kennedy in 1994.”

Santorum's Kennedy comment could be a reference to Romney's pledge to gay GOP group Log Cabin Republicans that if elected to the Senate he would do more to advance “full equality” for gay men and lesbians than his Democratic rival, the late Kennedy.

Santorum added that “desperate people do desperate things.”