Updated

Herman Cain plans to make an announcement Saturday about his political future, as his campaign reels from new allegations about an extramarital affair.

Cain previously had said he was taking a "reassessment" of his presidential campaign in light of the allegations of the affair and additional claims of sexual harassment. He denies the claims but is heading home to Atlanta to confer with his wife, saying his family is his "No. 1 priority."

Such comments have fueled speculation that Cain will drop out of the Republican race, but speaking Friday to supporters in South Carolina, he said only that he would make an announcement Saturday.

"Nobody is going to get me to make that prematurely," he said. "That's all there is to that. So tomorrow, we're going to be opening our headquarters in northwest Georgia, where we will also clarify ... exactly what the next steps are."

Cain earlier told Fox News that while he's spoken with his wife Gloria every day this week, he'll be at home Friday "so we can sit down and talk face to face."

After a woman came forward claiming a 13-year extramarital affair with Cain, the candidate has insisted his family is his No. 1 consideration as he weighs whether to scratch his campaign altogether.

Cain told Fox News on Thursday his wife does not doubt his vehement denials about the charges against him -- including prior sexual harassment allegations -- but the "media frenzy" is taking an emotional toll on his family.

"Many of my supporters, the response has been overwhelmingly positive that they are behind me, but I've got to consider family considerations first," Cain said.

He said he could either decide to campaign "full speed ahead" or suspend his campaign. He said he would be willing to end the campaign if his wife asked him to -- though Cain added that his wife wouldn't do that, and the decision will be his to make.

The critical juncture for the Cain campaign comes as he loses traction quickly in the polls following his improbable, albeit brief, rise to the front of the pack. Former House Speaker Newt Gingrich has moved up to eclipse even former Massachusetts Gov. Mitt Romney in some national polls, while Cain has fallen back -- along with fellow former front-runner Texas Gov. Rick Perry.

Already facing sexual harassment claims, Cain was hit with another blow when a woman named Ginger White came forward claiming an affair. Cain says he was only helping her out financially, and that they did not have an intimate relationship.

"Unfortunately, I'm a softy, and I feel sorry for people when they get in deep financial trouble," he told Fox News. "This isn't the only person I have helped."

He has acknowledged his wife did not know about their arrangement, but said he was also helping a male friend financially, which his wife didn't know about either.

While Cain's reassesses, his advisers are giving the impression of a campaign in motion.

"We're in it to win it," Cain's chief of staff Mark Block told the campaign's Iowa operation on Thursday.

Block's "unequivocal message," Iowa communications director Lisa Lockwood told Fox News, was that the Cain train is still moving "full steam ahead."

A new television ad will start airing in Iowa statewide Friday, entitled "Time to Put America Back to Work." In an email to supporters touting the ad, the campaign emphasized Cain's ability to create jobs and, in a cursory gesture toward White's allegations of infidelity, said "It's no secret that the Democrat Party and their surrogates in the mainstream media are out to derail Herman Cain's candidacy, and the only way for them to succeed is to destroy him personally."

Cain earlier this week made a string of campaign stops in the battleground state of Ohio.

Cain told Fox News on Thursday he'll also have to check the pulse of his donors. "Like a businessman ... when you have a bump in the road, you reconsider and reevaluate," he said.