Arnold Schwarzenegger has confessed to behaviour that "offended people" after a newspaper reported that he sexually harassed women over a 25-year period.
The Schwarzenegger campaign denies the allegations
The actor, who hopes to be voted in as Governor of California in next week's election, apologised after six women accused him of sexual harassment between 1975 and 2000, in an article in Thursday's Los Angeles Times.
They allege that he grabbed their breasts or buttocks, tried to take off a woman's bathing suit, and asked a woman if a particular sex act had been performed on her.
But after fending off one potentially damaging smear, Mr Schwarzenegger was forced to counter allegations that he once said he admired Adolf Hitler.
A report on the ABC Evening News claimed that Mr Schwarzenegger, in an interview 25 years ago, had said the Nazi leader was one of his heroes.
Asked to comment on that allegation, the Austrian-born actor said he could not imagine making such remarks and added that he despised everything the Nazis stood for.
Regarding the allegations of sexual harassment, Mr Schwarzenegger said he had sometimes behaved badly and added that things that he then thought were playful, he now realised had offended people.
"Those people that I have offended, I want to say to them that I am deeply sorry about that and I apologise because that's not what I'm trying to do," he told a stunned crowd in San Diego on Thursday.
The actor turned politician has sprung into the lead in the latest opinion polls and received crucial backing from Republican Party members.
A Los Angeles Times poll on Tuesday suggested that a majority of voters favoured removing the incumbent governor, Gray Davis.
Mr Schwarzenegger led the pack of more than 130 candidates vying to replace him, polling 40% support to second-place Cruz Bustamente, the Democrat lieutenant governor, polling 32%.
The Los Angeles Times opposes the recall of Mr Davis, and has accused Mr Schwarzenegger of failing to deal seriously with issues affecting the state.
Governor Davis is fighting for his political life
It also said in a 28 September editorial that he "seemed to have only a casual acquaintance with the truth as practised outside Hollywood".
The newspaper says it confirmed that the women had told their stories to other people before Mr Schwarzenegger began his race for governor.
Three of the women said he had grabbed their breasts, while a fourth said he placed his hand under her skirt on her buttock.
A fifth woman says Mr Schwarzenegger tried to take off her bathing suit in a hotel elevator, while the last says he pulled her onto his lap and asked her about a particular sex act.
Four of the six women asked to remain anonymous.
The other two are E Laine Stockton, the former wife of bodybuilder Robby Robinson, and the British television presenter Anna Richardson.
Both said Mr Schwarzenegger had squeezed their breasts.
Three of the women said they work in Hollywood and fear retaliation if they make their accusations publicly.
Several said Mr Schwarzenegger's star power had made it impossible to do anything about his alleged behaviour.
"What could you do? He was the highest-paid actor in the world. I was a peon. All you could do was stay away from him," said the woman who claims he tried to remove her bathing suit.
She said it happened "at least three times, if not more" when she was working on the crew of his film Terminator 2 in 1990.
The Los Angeles Times said that many people interviewed for the article said the tone on movie sets tends to be rowdy.
Several people described Mr Schwarzenegger's sense of humour and language as "outrageous, but not mean-spirited".
One stuntwoman who worked with him on a number of films defended him.
"He's fun, extremely intelligent and very professional," she told the newspaper.