Republican Herman Cain faced the toughest challenge of his upstart US presidential campaign today over sexual harassment allegations that surfaced just as he was riding high in the polls.
The former pizza executive, whose campaign team decried "unsubstantiated personal attacks," talked about taxes at a Washington think tank and tried to ignore the controversy.
He acknowledged that he was accused of sexual harassment in the 1990s but called the accusations "baseless."
"I have never sexually harassed anyone," Mr Cain said. "Yes, I was falsely accused while I was at the National Restaurant Association."
The news website Politico reported two women employees complained of sexually suggestive behavior by Mr Cain when he headed the National Restaurant Association in the 1990s.
"Herman Cain has never sexually harassed anybody. Period. End of story," his chief of staff, Mark Block, said on MSNBC.
The report could damage Mr Cain's surprisingly strong bid to be the Republican challenger to Democratic President Barack Obama in the November 2012 election.
At the American Enterprise Institute, Mr Cain focused on his signature 9-9-9 economic plan that would throw out the US tax code and replace it with 9 per cent tax rates on personal and corporate income plus a 9 per cent national sales tax.
When someone at the event tried to ask Mr Cain about the allegations, the moderator said the question was not appropriate for the forum.
Mr Cain was also due to appear at Washington's National Press Club, where the allegations were likely to come up.
Mr Cain (65) has been an unlikely front-runner, competing with former Massachusetts Governor Mitt Romney for the lead in polls of Republican voters with two months until primary elections start to choose the party's 2012 presidential nominee.
Politico said at least two female employees complained to colleagues and senior restaurant association officials that inappropriate behavior by Mr Cain made them angry and uncomfortable.
The women ultimately left the trade group after signing agreements that gave them payouts and barred them from talking about their departures, the report said.
"I would suggest that you contact the National Restaurant Association and ask them about any settlement. I am not personally aware of any settlement dealing with Mr. Cain," Mr Block said on MSNBC.
The allegations could be critical in Iowa, where evangelical conservatives are a dominant voice and where Mr Cain holds a narrow lead in the polls ahead of the state's January 3 caucuses, the country's first 2012 nominating contest.
"The people have propelled my candidacy," Mr Cain said of Republican skepticism of his candidacy. "The party may resist and I'm not saying that they are. I'm not the party favorite by some members of the party. I understand that."
Mr Cain also courted controversy with a Web advertisement last week that showed his chief of staff smoking.
Bob Schieffer, who hosts the Face the Nation news program on CBS, scolded Mr Cain about the ad yesterday, saying it looked like his campaign was endorsing smoking.
"Yes, I am an unconventional candidate," Mr Cain said at the think tank. "Herman is going to stay Herman."
Mr Block, asked if he had spoken to Mr Cain about the harassment allegations, said: "He said to me emphatically 'When there are facts, bring them to me. Let me face my accusers and we'll deal with it then.'"
Republicans have struggled to find a front-runner with conservatives seeking an alternative to the more moderate Romney. Minnesota Congresswoman Michele Bachmann, Texas Governor Rick Perry and now Mr Cain have attempted to fill that role.
Agencies