New Republican presidential frontrunner Mike Huckabee is "categorically" denying that while governor of Arkansas he tried to pressure the parole board to release a convicted rapist who later went on to rape and murder a Missouri woman.

Huckabee, who is surging in recent primary polls, has been called on to defend his record, following reports that he played an active role in seeking the release of prisoner Wayne Dumond.

"No. I did not. Let me categorically say that I did not," Huckabee said Tuesday, adding that while governor he denied a request for Dumond's commutation.

Huckabee acknowledged that shortly after becoming governor in 1996 he did visit the parole board — all appointees of his predecessors, Bill Clinton and Jim Guy Tucker — so he could offer his views on crime and parole in general, and the Dumond case came up during that meeting.

Huckabee also reportedly wrote a letter to the convict expressing his wish that he be paroled.

“My desire is that you be released from prison. I feel that parole is the best way for your reintroduction to society to take place," Huckabee wrote in the 1996 letter obtained by National Review Online.

Click here to read the National Review Online article.

The Dumond case is long and graphic. In 1984 at age 35, Dumond was charged with the rape of an Arkansas cheerleader who was a distant cousin of Bill Clinton's. While awaiting trial and out on bond the next year, two unidentified men entered Dumond's home, tied him up and castrated him. His testicles were later displayed in a jar of formaldehyde on the local sheriff's desk. No one was ever charged for that crime.

In 1992 Tucker reduced Dumond's sentence of life plus 20 years to make him eligible for parole. Huckabee said Tuesday that Dumond had an "unblemished prison record," and that he met all the qualifications for parole, including having a job lined up and a sponsor with a church.

Dumond was paroled by the board in 1999. But shortly after his release Dumond moved to Missouri where he raped and murdered Carol Sue Shields. He was convicted and sentenced to life in prison in Clay County, Mo., in 2003. He died in prison in 2005.

Shields' mother, Lois Davidson, blames Huckabee for her daughter's murder.

"I can't imagine anybody wanting somebody like that running the country," Davidson told ABC News.

The news agency also reports that a former parole board member claimed Huckabee exerted pressure on the board to free Dumond. Huckabee denies that charge.

"I did not ask them to do anything," he said. "I did indicate it was sitting at my desk, and I was giving thought to it."

Huckabee said the Shields murder was a "horrible situation" and that he would reverse the clock and put Dumond back in prison if he could, but that nobody could have anticipated Dumond's crime.

"For those people to say that I was responsible in getting him out makes a few presumptions," Huckabee said, noting that Tucker had commuted Dumond's sentence years earlier, the seven-member Democratically-appointed panel would all have had to been influenced by a new Republican governor and that two board members who changed their stories did so six years later in an election year, after having not been reappointed to their posts.

"Now if you can follow that line and believe that I am solely responsible then you'll believe that. But you'll believe a lot of other things as well," he said.

The brutal tale seems to be catching fire on the campaign trail just as Huckabee has taken a lead in some polls. A new Rasmussen daily tracking poll released Wednesday showed Huckabee leading the GOP field nationally for the first time, with 20 percent. Rudy Giuliani, the frontrunner in most national polls, clocked in with 17 percent. In an Iowa poll out last week, Huckabee led Mitt Romney 29 to 24.

The Dumond case is not the first time a past judicial decision has haunted a candidate on the trail.

Romney in November found himself having to answer for the actions of a Massachusetts Superior Court judge he nominated while governor who released a convicted killer later held in the murders of a Washington state couple.

Both cases raise the specter of Willie Horton, whose criminal actions tripped up the campaign of former presidential candidate and Democratic Massachusetts Gov. Michael Dukakis, who had maintained a weekend prison furlough program under which Horton, a convicted murderer, was granted a furlough in 1986. In 1987 he raped and beat up a Maryland woman and her fiancé. The issue helped cause insurmountable damage to Dukakis' 1988 general election campaign against GOP nominee George H.W. Bush.

Huckabee said Tuesday that he expected the Dumond case to continue to surface in the presidential campaign.

"There will be people who are victims who will probably be brought forth to make statements, but, you know, I can't fix it," he said. "I can only tell the truth and let the truth be my judge."