Indian-American Nikki Haley, whose bid for the governorship of South Carolina is marred by allegations of extra-marital affair, suffered a setback on Thursday when former vice president Dick Cheney endorsed one of her rivals.
"Today, I am strongly endorsing Gresham Barrett," Cheney said in a statement in the run-up to the June 8 gubernatorial primary of the Republican Party.
Barrett is trailing in the polls behind state Nikki Haley and Attorney General Henry McMaster.
The most recent poll on the race conducted by Public Policy Polling had Haley at 39 percent, McMaster at 18 percent, and Barrett at 16 percent, followed by Lt.Gov Andre Bauer at 13 percent.
"Gresham Barrett is one of the most conservative leaders I've ever worked with. No one in South Carolina has done more to fight President Obama's reckless agenda than Gresham Barrett," Cheney said.
Meanwhile, Haley continued to surge ahead of all her rivals and the popular mood in South Carolina - as reflected in local news reporting -- questioned the authenticity of the allegations made by a blogger against her that he had an affair with the popular Indian American leader.
"If proof doesn't surface or doesn't exist, many say Haley, surging in some polls and recently endorsed by former Alaska Governor Sarah Palin and former SC first lady Jenny Sanford, is in solid shape heading into the June 8 primary," said The State, South Carolina's main newspaper.
The 38-year-old mother of two, whose husband is a US Army reserves officer, has been hit by allegations that she had a "physical" relationship with commentator Will Folks.
The claims are threatening to derail her campaign to replace the disgraced former governor Mark Sanford, who fell from grace after he was forced to admit having an affair.
If elected, she would be only the second governor of Indian origin in the US after Louisiana's Bobby Jindal.
"I have been 100 per cent faithful to my husband throughout our 13 years of marriage. This claim against me is categorically and totally false. It is quite simply South Carolina politics at its worst," Haley said.
"This disgraceful smear has taken form less than a week removed from the release of a poll showing our campaign with a significant lead," she said in a statement.
The controversy erupted when Folks posted a statement on his website claiming that "several years ago, prior to my marriage, I had an inappropriate physical relationship with Nikki. That's it".