UPDATED 11/08/11 7:10 a.m.

CHICAGO (CBS) — Herman Cain has flatly denied claims the latest claims of sexual harassment by a Chicago area woman, in what is now one of numerous allegations against the Republican presidential candidate.

Cain is set to hold a news conference about the allegations at 4 p.m. Tuesday. But on ABC’s “Jimmy Kimmel Live” Monday night, he denied the graphic claims by Sharon Bialek, of Mundelein, that he groped her in 1997. He also denied the other past sexual harassment allegations that have surfaced recently.

“There’s not an ounce of truth to any of these allegations,” Cain said on the program. “That’s why I’m willing to do a press conference tomorrow to set the record straight.”

He said he is furious about the allegations and those who have brought them.

“I had a few of my staff members with me, and I’m sitting there, and they’re watching me, and they could see steam coming out of my ears,” Cain said on the program, “and the feelings that you have when you know that all of this is totally fabricated, you go from anger, then you get disgusted.”

He went on to say that his policies and campaign message out, such allegations are irrelevant.

“When people believe in Herman Cain and his message, they know that it is sincere, and so they’re not swayed by what they call in politics the flavor of the week,” Cain said on “Jimmy Kimmel Live.”

In response to Cain’s latest remarks, Bialek said on the CBS Early Show that he should just admit to what happened.

“I don’t despise the man,” she said. “I actually did it because I want to help him. I want to give him a platform to come clean; to tell the truth, and he still hasn’t done it, and it’s really a shame.”

Bialek said someone needed to come forward with allegations.

“I wanted to be the voice and the face for those women who couldn’t or wouldn’t come forward, and those that know me know that I’m pretty outspoken and I fight for my convictions, and I really believe in this and I have to do something,” she said.

CBS 2’s Mai Martinez reports Bialek’s claims are potentially the most damaging for Cain so far, not just because she was the first accuser to come forward publicly, but because she left little to the imagination about the alleged harassment.

“He suddenly reached over and he put his hand on my leg, under my skirt and reached for my genitals,” Bialek said of her encounter with Cain in 1997. “He also grabbed my head and brought it towards his crotch.”

Bialek worked for the Educational Foundation of the National Restaurant Association in 1996 and 1997. Cain ran the trade group at the time and Bialek said she first met him at a trade convention.

She said they sat next to each other during a couple of dinners and at a luncheon at the association convention in Chicago in 1997. Bialek said she was so inspired by a speech Cain gave that, “when he sat down, I said to him ‘When are you running for president?’”

About a month after the convention, Bialek was fired from her job for not raising enough scholarship money and her boyfriend suggested she reach out to Cain for help.

Bialek said she did and Cain agreed to meet her in Washington, D.C., while she was visiting friends.

Bialek said she later learned Cain upgraded her hotel room to a suite, but didn’t push the issue as the two went to dinner.

After that dinner, Bialek claimed, Cain crossed the line while the two were in a car headed back to the hotel. She said Cain offered to show her the association offices, and then the groping began.

Bialek said she told Cain to stop and he did, then drove her back to her hotel.

Bialek is being represented by attorney Gloria Allred, who said that Bialek is not filing a lawsuit or other legal claim against Cain. Bialek said she just wants Cain to acknowledge harassing her.

Allred noted on the Early Show that Bialek is a registered Republican and has not endorsed any other candidate, and all she wants is for Cain to admit to his actions.

Meanwhile, WBBM Newsradio’s Steve Miller reports Bialek’s fiancé , Mark Harwood, said her decision to speak out “took some guts.”

Harwood, who lives with Bialek in Mundelein, tells WBBM Newsradio that Bialek is “true blue” and has a “good heart,” and he says, “I’ll back her 100 percent.”

LISTEN: WBBM Newsradio’s Steve Miller Reports

He echoed Bialek’s remarks it was time for someone to come forward, after the first three women to allege sexual harassment by Cain chose to remain anonymous.

“You’re looking for a new president in the U.S. next year,” he said. “I don’t think it necessarily sits well that you’ve got potentially somebody that running for candidacy and lying about some serious issues.”

In a new development, a fifth woman has also now accused Cain of questionable behavior.

The Washington Examiner reports Donna Donnella, of Arlington, Va., said Cain asked her to help arrange a dinner date with a woman he spotted in the audience at a speech he gave in Egypt. When Donnella declined, Cain allegedly asked her to dinner instead.

Donnella is not accusing Cain of any sexually inappropriate conduct, but he did order two $400 bottles of wine and let the women pay for them, the Examiner reports.

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