WASHINGTON Republican U.S. presidential candidate Herman Cain accused rival Rick Perry's campaign on Wednesday of being behind explosive sexual harassment claims as the 2012 White House race erupted into acrimony.
Cain said his opponents were "trying to destroy me" and got testy with reporters demanding answers even as reports surfaced of a third woman claiming she was harassed.
Cain chief of staff Mark Block issued a scathing indictment of rival conservative Perry's camp which he said had spread false allegations.
"It's an outrage," Block told Fox News. "The Perry campaign needs to apologize to Herman Cain and his family and America for this despicable action."
Cain and Perry are fighting it out to be the main conservative challenger to former Massachusetts Governor Mitt Romney in the race for the Republican nomination to take on President Barack Obama next year.
Perry spokesman Ray Sullivan denied the charge that the Texas governor's team was behind the sexual harassment claims that surfaced last weekend in Politico news web site.
"Mr. Block's claims are patently false. No one at our campaign was involved in this story in any way," he said.
Cain, the former CEO of Godfather's Pizza, struggled to get control of the escalating crisis just as he is leading in many polls of Republican voters.
One accuser was seeking to tell her side of the story, raising the prospect of a media feeding frenzy.
"Don't even bother asking me all of these other questions that you all are curious about," Cain told reporters as he met with white-coated conservative doctors. "Excuse me!" he shouted testily when they pressed ahead with questions.
Cain's lead could be short-lived once voters absorb the drip-drip-drip of controversy emerging about the case, in which at least two women accused Cain of sexual harassment when he led the National Restaurant Association in the mid-1990s.
To add to the political acrimony, the Perry camp suggested Romney's campaign might have been responsible for the claims, but Romney spokeswoman Andrea Saul said, "Not true."
The controversy is a setback for Cain, whom a Quinnipiac University poll declared the front-runner in the Republican race with 30 percent, followed by Romney with 23 percent.
The poll was taken mostly before the allegations surfaced this week.
An Oklahoma political consultant with links to the Perry campaign, Chris Wilson, told local radio station KTOK he was a witness to one incident.
"I was the pollster at the National Restaurant Association when Herman Cain was head of it and I was around a couple of times when this happened and anyone who was involved with the NRA at the time, knew that this was gonna come up," he said.
Wilson said for legal reasons he could not discuss details of the incident, "but if she comes out and talks about it, like I said, it'll probably be the end of his campaign."
The Associated Press reported a third former employee said she considered filing a workplace complaint over what she considered aggressive and unwanted behavior by Cain when she worked for him. The behavior included a private invitation to his corporate apartment, she said.
"There are factions that are trying to destroy me, personally, as well as this campaign," Cain said, speaking to technology executives in a Virginia suburb of Washington.
The New York Times reported that one woman who accused Cain of sexual harassment had been given $35,000, a year's salary, in severance pay in the late 1990s after an encounter with Cain.
Joel Bennett, the lawyer for one of the women, said his client wants to be released from a confidentiality agreement that has barred her from speaking about her interaction with Cain.
The lawyer told MSNBC his client was subjected to more than one incident of sexual harassment. Cain has said he told that woman she was about the same height as his wife and that it was taken the wrong way by her.
The National Restaurant Association said the woman's lawyer contacted association officials on Wednesday and was asked to get in touch with the organization's outside counsel.
"Mister Bennett indicated that he would do so tomorrow (Thursday), after he met with his client," said Sue Hensley, a spokeswoman for the association.
Block told Fox it was up to the National Restaurant Association to decide what it wanted to do.
Travis Gemoets, a Los Angeles lawyer who specializes in this type of cases, said it could be that all three parties -- the woman, Cain and the restaurant association -- would have to agree to lift the confidentiality agreement.
Alternatively, he said, the woman could get an agreement from a third party to pay any penalties or legal costs she might sustain, freeing her up to tell her story without agreement from the other two parties.
"Typically these cases don't allow (a circumstance where) if one side breaches, that means the other side immediately can," Gemoets said.
Cain told the technology executives he expected his campaign would survive because of his popular support.
"There's a force at work here that is much greater than those that would try to destroy me, and destroy this campaign, and this journey to the White House. And that force is called the voice of the people," he said.
(Additional reporting by JoAnne Allen, David Morgan, Thomas Ferraro and Kim Dixon; Writing by Steve Holland)