By: Judy Woodruff

Rick Perry did Herman Cain a favor in the Michigan GOP debate. By failing to remember the name of the third federal agency he intended to shut down if elected president, he claimed unflattering next-day headlines that might have otherwise at least been shared by Cain.

When the former Godfather's Pizza executive was asked during the debate about sexual harassment charges leveled against him by several women, he again called them "unfounded," adding "I value my character and my integrity more than anything else."

If Cain is being truthful, and there is nothing to the allegations made by four different women and two other witnesses to incidents where Cain engaged in possibly inappropriate behavior, then this episode will eventually fade away.

It will be left at "she said, he said" phase with no corroborating evidence. The Georgia businessman will be able to stand on his repeated denials, and maybe even his charge -- still unproven -- that the claims are the result of "the Democrat machine."

Recent history, in fact, reminds us that prominent politicians have survived personal allegations, even acknowledged misbehavior, by sheer political skill. Often this means undermining the reputation of the women involved or attacking the reporter and the news organization covering the story. As Mark Halperin points out in an upcoming issue of Time magazine, both President Bill Clinton and Sen. John McCain managed to pull this off.

At the same time, modern political history is also replete with politicians who first denied, and later had to acknowledge, personal misconduct. In October 1974, then-legendary House Ways and Means Committee Chairman Wilbur Mills, D-Ark., initially denied, through spokesmen, that he was in a car with an Argentine stripper, Fanne Fox, when it was stopped at 2:00 a.m. near Washington's Tidal Basin. Later, he had to admit he'd not only been there, but he'd been drinking heavily, and had had a personal relationship with her for several months. After a second public episode, he stepped down from his chairmanship, and went into treatment for alcoholism.

In May 1987, then Sen. Gary Hart of Colorado, who had recently announced he was running for the Democratic nomination for president, was confronted by reporters from the Miami Herald, after they saw a young woman enter his Washington townhouse, not to reappear until the next day. Asked initially about rumors of womanizing, Hart had said, "Follow me around, I don't care ... if anybody wants to put a tail on me, go ahead. They'd be very bored." On the day reporters did just that, Hart continued to insist he and the woman had no relationship. A week later, he dropped out of the race, criticizing the news media.

Then, in January 1998, President Bill Clinton famously denied having had "sexual relations" with Monica Lewinsky, before his acknowledgement that August that, indeed, he had engaged in "an improper relationship" with the former White House intern.

Of course the most easily recalled from the past few years is former Democratic Vice Presidential nominee John Edwards, who first vigorously denied he had an extramarital affair with a former campaign worker, then, in 2008 admitted it was true. He continued to deny he had fathered her child, but last year, finally acknowledged that as well.

The misconduct of all these successful public figures varies, but the pattern has been identical: first, deny; only acknowledge when confronted with evidence or compelling testimony otherwise. Cain's favorability ratings are starting to slip, but without further proof, and with a loyal conservative fan club, he just may overcome this.

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