Keith Olbermann has been taking heat from his critics for his blistering characterization on Monday's Countdown of then-candidate Scott Brown. On Tuesday night he blasted back.

"I wanted to apologize for calling Senator-elect Scott Brown an irresponsible, homophobic, racist, reactionary, ex-nude model, tea-bagging supporter of violence against women and against politicians with whom he disagrees," Olbermann began.

"I am sorry," he went on. "I left out the word sexist."

Conservative blogs had condemned Olbermann's original remarks, using words like obscene, shameful, and despicable. Even Olbermann's fellow MSNBC host Joe Scarborough described the attack on Brown in a Twitter post as "reckless and sad."

"For all the blowback from the right on this comment," Olbermann responded on Tuesday, "from people who regularly mutter worse things about Barack Obama in their sleep, when it came to the facts that I cited to paint this picture of this horrifically unqualified senator-elect, we have heard nothing. No contrary evidence, no refutation, not even a plausible excuse."

Olbermann focused in particular on his description of Brown as a "supporter of violence against women and against politicians with whom he disagrees." He pointed out that even if you accept the explanation that Brown didn't hear the call from a member of his audience to shove a curling iron up Martha Coakley's butt, "Where was his later statement decrying the obscenity and violence his supporter had suggested?"

"If he or you don't like that characterization, my answer to you is simple," concluded Olbermann. "Disprove it. Because he hasn't."

This video is from MSNBC's Countdown, broadcast Jan. 19, 2010.

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