And so Cain did what he always does: He turned a devastating situation to his advantage. "By the way, folks, yes, I am an unconventional candidate," he told the overflowing crowd. "And, yes, I do have a sense of humor. And some people have a problem with that. But ... Herman is going to stay Herman."
So the women who filed the complaints didn't get his sense of humor? And that's the end of it?
It just may be. This sort of scandal would end the career of many a politician. But the usual rules don't apply to Herman Cain. He survives gaffes and scandal the way he beat colon cancer - and whatever doesn't kill him makes him stronger.
He says he would negotiate a swap of terrorists at Gitmo - then claims he misunderstood the question. He claims abortion should be an individual choice - then again says he misunderstood. He proposes an electrified border fence that could kill immigrants from Mexico - then says people didn't get the joke.
Evidence that he has said something dumb or offensive only confirms to his supporters that he is not another polished pol like President Obama or Mitt Romney. And so Cain doesn't need to know what a neocon is, he can weather campaign-funding irregularities, he can have his chief of staff blow cigarette smoke in a campaign ad, he can skip the early primary states in favor of a book tour of the South, and he can sing about pizza to the tune of John Lennon's "Imagine."
This allows Cain to perform as a self-parody on the campaign trail, confident that whatever absurdity he comes up with will only add to his outsider mystique. Arriving on stage for the AEI speech, he began by asking that his microphone be turned down because "I'll blow this thing to smithereens."
He then proceeded to blow up the usual political constraints. He responded to a British reporter with a phony English accent. When asked about energy policy, Cain said he'd get to it on day two of his administration. "Day one, I'm going to take a nap." Asked about his prospects for remaining a top-tier candidate, he replied: "This flavor of the week is now the flavor of the month, and it still tastes good."
Cain's hosts at the AEI had forbidden any questions about the sexual harassment claims; ABC's Jonathan Karl had the microphone taken from him when he tried to ask about the "big cloud" over Cain. That had the effect of moving the reporters' interest to Cain's second appearance of the day, at the National Press Club.
"I have never sexually harassed anyone," the candidate said there. If the Restaurant Association paid a settlement, "I hope it wasn't for much." (Later in the day, he acknowledged remembering one of the settlements.)
So would he ask for records of the investigation to be released in order to shoot down the allegations? "No, there's nothing to shoot down," he replied, and "the policies of the Restaurant Association is not to divulge that information."
Nothing to see here. Move along. And Cain did. He had more fun with his signature policy proposal ("How did we come up with 9-9-9? Why not 10-10-10; why not 8-8-8?"). And he asserted his belief that life imitates the pizza business. "The way we renewed Godfather's Pizza as a company is the same approach I will use to renew America."
When asked to go beyond the slogans, Cain requested a lifeline, inviting adviser Rich Lowrie to answer the question for him. Though letting his aide field the tough stuff, Cain was happy to handle the final question - a request for a song. This time, he crooned a few bars from the hymn "He Looked Beyond My Fault."
For Cain and his forgiving supporters, it could be a theme song.
Dana Milbank is a Washington Post columnist. He can be reached at email@example.com.