William Gheen, the leader of an anti-illegal immigration group, has received considerable attention after asking Sen. Lindsey Graham (R-SC) to admit he’s gay — an unsubstantiated allegation — before liberals can use it against him.

Comedy Central’s Stephen Colbert slammed Gheen Thursday and quipped, “Lindsey Graham, save your good name by releasing a sex tape!”

“Nine times out of ten I’m on the side of whoever is calling somebody gay,” Colbert said. “But the person being accused here is a senator from my home state, an I’m not going to let someone slander his good name.”

Graham, who has been the target of rumors about his sexuality for years,Ã‚Â says he’s not gay. In this case, he was arguably targeting by Gheen because he is one of a few Republican senators willing to negotiate with Democrats for immigration reform.

“I hope this secret isn’t being used as leverage over Senator Graham, so today I think Senator Graham, you need to come forward and tell people about your alternative lifestyle and your homosexuality,” Gheen told a Crowd of Tea Partiers in South Carolina last weekend.

The remarks went viral after they were posted on YouTube by his group, Americans for Legal Immigration PAC (ALIPAC). At one point, the video was marked with the tags “queer” and “fag.” ALIPAC claimed that their video page had been hacked and the tags were soon removed.

“I have to admit, that was very brave of Mr. Gheen. Outing someone usually takes the kind of courage only displayed by male prostitutes paid by tabloid magazines,” quipped Colbert in his “The Word” segment Thursday.

Colbert looked to an old “Sex and the City” episode for ways the senator can clear this up permanently. In season six, Kim Catrall’s character is determined to quash rumors that her male model boyfriend is gay, and decides that only by making a sex tape can her man prove he’s straight.

“Sir, it will save your career,” Colbert said. “Because any kind of straight sex seems to be okay with the GOP. I mean, just look at Governor Mark Sanford, Senator John Ensign or Senator David Vitter, who is still in office despite being named as a client by the D.C. madam three years ago and dogged by rumors that he allegedly likes prostitutes to dress him up in diapers.”

“So just rent the equipment. Hell, rent the girl. Just put it in there and get it out there,” Colbert suggested.

At that, Colbert turned his attention to Gheem. “He’s a big opponent of illegal immigration, and the immigration reform bill is the next big piece of legislation in Obama’s pipeline. Now, Gheen knows the Republicans only have 41 seats in the Senate. To block legislation, they have to march in unison. So the real threat is not the fact that Lindsey Graham is gay, which he isn’t, it’s that he’s bi, which he is, bi-partisan,” the comedian said.

Gheen has suggested Graham may be getting blackmailed into bipartisanship, but the activist hasn’t targeted other Republican senators — such as Sens. Olympia Snowe (ME), Susan Collins (ME) and Scott Brown (MA) — who have voted with President Obama on initiatives.

Even Gheen seems to swing both ways. “I just found out that he worked with the Democratic party in the 1990s. That sounds pretty bipartisan,” Colbert said.

Based on that fact, Colbert turned the tables in Gheen. “I’ve got to at least consider the possibility that someone found out he gets off by going to the ballpark on weekends and laying in a trough in the men’s room like a human urinal cake. I have got nothing to back that up. I just need to know that that’s not true,” he concluded.

This video is from Comedy Central’s The Colbert Report, broadcast April 22, 2010.

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