In an affidavit to a group of Republican activists critical of Haley, Will Folks states he had "romantic encounters" with the state representative in her Cadillac SUV, his apartment and her Statehouse office. He said the physical relationship ended in June 2007, when he began dating the woman who is now his wife.
"Rep. Haley specifically requested that I notify her in the event this relationship was getting serious so that she could 'back off,"' the statement reads.
Haley's campaign again denied all of Folks' claims, which were made without any proof.
"There is something about the days just before an election that make certain people want to get back in the newspapers," said Haley campaign manager Tim Pearson. "These accusations weren't true in June, they aren't true now, and those who continue to be fixated on this nonsense really should look into getting some professional help."
Folks, 36, provided the three-page affidavit to the two-week-old group calling itself Conservatives for Truth in Politics, which is questioning Haley on various issues. It was sworn before a South Carolina notary public and signed by both but is not filed in any court.
The conservative group is clearly critical of Haley but says it will not endorse her or her opponent, Democratic state Sen. Vincent Sheheen. Lobbyist Larry Marchant, who came forward to say he had a one-night stand with Haley in 2007, told The Associated Press he, too, will provide an affidavit to the group.
"I have determined that your request for the production of a 'signed and sworn affidavit' attesting to the veracity of my previous public comments is reasonable," Folks wrote in an e-mail to the group's co-founder Cyndi Mosteller, former vice chairwoman of the state Republican Party and former Charleston County GOP chairwoman.
Haley, a 38-year-old married mother of two, has repeatedly vowed she has been faithful over 13 years of marriage. Folks' allegations, first made on his website in May, appeared to only bolster her tea party-backed campaign against what she's characterized as an establishment political system.
The detailed claims come as a new poll by Winthrop University shows Haley with a 9 percentage-point lead over Sheheen -- 46 percent of likely voters said they plan to vote for her, compared to 37 percent for Sheheen; 13 percent say they're undecided.
Folks, a former spokesman for Gov. Mark Sanford, said in his statement that he worked for Haley from early 2007 until March 2008 as a consultant. He said they first kissed in early 2007 outside a bar in downtown Columbia after an evening with friends, then parked behind a neighborhood center at a local park.
He said they usually met at a bar in a neighborhood near the University of South Carolina or another restaurant in Columbia. Folks has said he came forward with his allegations to preempt the work of political operatives and reporters about to expose the 2007 relationship with Haley, his favored candidate and former employer.
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He said he believes e-mails addressing the allegations could be found on Haley's computer hard drive. She has allowed reporters to review thousands of e-mails, which spanned several months earlier this year, from one of her legislative e-mail accounts.
The affidavit was first reported online Tuesday by the Charleston City Paper.
Folks wrote they had an "inappropriate physical relationship" and gave no solid proof. He did make public phone records that detailed lengthy, late-night calls between the two.
Marchant, who is married, resigned from a rival primary campaign. Though he came forward with an allegation of his own tryst with Haley, he also said he had no proof. He said he spoke up after rumors in political circles resurfaced following Folks' claims, and Haley's statements that she had been faithful to her husband prompted him to confess to his wife.
Haley responded in speeches and campaign ads talking about the rougher side of campaigning.
"I've seen the dark side of our state's politics, and I know the bright side of our state's people," Haley said in one spot, with images of husband Michael and their two children. "I have a vision of what South Carolina can be."