Herman Cain has scheduled a press conference in Phoenix on Tuesday to address charges of sexual harassment from Sharon Bialek, who became the fourth woman to allege inappropriate behavior from the GOP primary candidate. As Natalie Jennings reported:

Herman Cain’s rivals have avoided weighing in on the sexual harassment allegations that have cropped up over the course of the past nine days as Cain prepares to address them again today in a 5 p.m. ET news conference.

ABC News and Yahoo are streaming live interviews with each of the major Republican presidential candidates today, but none of them have been very willing to entertain questions about the scandal.

Jon Huntsman: It’s a distraction and Herman Cain can deal with it however Herman Cain chooses to deal with it... Far be it from me to advise Herman Cain

Michele Bachmann: I don’t have any information about these allegations whatsoever. I have absolutely nothing to contribute to that discussion.

Mitt Romney: These are serious allegations and they’re going to have to be addressed seriously.

Among political activists, however, there is evidence of a shift in sentiment toward Cain. Jennifer Jacobs of the Des Moines Register interviewed several Iowa conservative leaders after Sharon Bialek came forward Monday with her account of an inappropriate incident with Cain.

Bob Vander Plaats, one of the most prominent evangelical leaders in Iowa, called the incident “a tipping point for the viability of his campaign,” though some Republican pundits remain skeptical of the allegations, as the Fix’s Rachel Weiner reported Monday.

Cain has denied the charges and today his campaign questioned the motives of Bialek and her attorney Gloria Allred.

Sharon Bialek, the latest woman to bring allegations against Cain, said on Monday she was not offered money to come forward, but that it was “the right thing to do”. As Nia-Malika Henderson explained :

The woman accusing GOP presidential contender Herman Cain of unwanted sexual advances said she was not paid or promised any employment in exchange for making her allegations publicly.

“I’m just doing this because it’s the right thing to do,” Sharon Bialek told ABC in an interview Tuesday morning.

She and her lawyer criticized Cain for seeming to make light of the allegations that Cain groped under her skirt and sought a sexual act when she came to him for advice on getting a job more than a dozen years ago.

“I don’t think there is anything funny about this subject,” Bialek, a Chicago homemaker and single mother. “And for him to do that is just deplorable.”

Cain, who at the time headed the National Restaurant Association, vehemently denied the harassment allegations in a television appearance Monday night. After days of refusing to discuss the specifics of the allegations being made against him, he has scheduled a news conference for Tuesday afternoon to ”set the record straight.”

“There is not an ounce of truth in all of the accusations, and my team is putting this stuff together,” he said Monday. “That’s why I’m willing to do a press conference.”

Bialek, the fourth woman to make allegations against Cain but the first to do so publicly, said lawyer Gloria Allred has taken her case pro-bono. Bialek denied suggestions by the Cain campaign that she was given money or promised a job in return for making her allegations publicly.

Cain has suggested that the allegations against him are both racially motivated and orchestrated by the campaign of Texas Gov. Rick Perry, which Perry has denied. But Bialek said that she has not had any contact with any other Republican presidential campaign.

Appearing on both ABC’s “Good Morning America” and CNN, Bialek insisted that she was telling her story to give a voice to the other allegations, which involve women who have chosen not to come forward. She urged Cain to be upfront at his news conference later Tuesday.

“It’s not too late. He can step forward and just end it,” Bialek said. “I don’t want to be here. I don’t think anyone wants to. End it by saying ‘I did these things.’”

As allegations pile up against the businessman, many analysts are asking if his campaign can survive the harassment allegations. As Perry Bacon Jr. and Dan Eggen reported:

Republican presidential hopeful Herman Cain faced a new set of political challenges Monday after graphic allegations by a Chicago woman raised questions among GOP operatives and activists about the candidate’s ability to survive the growing scandal.

After eight days of accusations and denials of alleged sexual harassment by Cain, the specific and explicit nature of the new allegations could threaten his position among a core group of supporters who have stood by him, or at least stayed silent.

“This is the first time that the allegations have been about physical rather than verbal harassment. These are much more serious charges that require Cain to provide a more specific explanation than a blanket denial,” said Daniel Schnur, who advised Sen. John McCain’s 2000 presidential campaign but is uncommitted in the 2012 contest.

Mississippi Gov. Haley Barbour told the conservative magazine National Review on Monday: “If there is any substance to the claims, if the American people believe that somebody abused women, they are not going to elect him or her president. If this were taken as being true, and people believe it’s true, then I don’t think that can be overcome.”

The initial allegations against Cain — dating to the 1990s, when he was chief executive of the National Restaurant Association — were general and unspecific, and Cain denied them.

Sharon Bialek changed that Monday with a nationally televised news conference in which she accused Cain of groping her and trying to force her into a sexual act.

Cain’s campaign issued another denial but did not respond directly to Bialek’s claims: “All allegations of harassment against Mr. Cain are completely false,” said J.D. Gordon, a Cain spokesman. “Mr. Cain has never harassed anyone.” Gordon characterized Bialek’s charges as “bogus attacks.”

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