Huckabee had once spoken in favor of releasing the man but told reporters the decision to do so was made by parole board members appointed by his Democratic predecessors, Jim Guy Tucker and Bill Clinton.
Huckabee said he could not remember all the details of a meeting he had with parole board members during which the case of Wayne DuMond came up. But he asserted, "I didn't try to, you know, push anybody's buttons on it."
Two months after taking office in Little Rock, Huckabee announced he favored DuMond's early release because he doubted the inmate's guilt and because DuMond had been castrated while awaiting his rape trial. DuMond said masked men attacked him at his home, but no one was ever charged.
DuMond initially was sentenced to life plus 20 years for his conviction in the 1984 rape of a teenager, but Tucker reduced the sentence to 39½ years, making DuMond eligible for parole.
Huckabee later denied clemency on the same day the state parole board, reversing its earlier decision, granted DuMond parole.
DuMond was released to Missouri in 1999 where he was charged in the murder of a Kansas City-area woman. He died of cancer in prison in 2005.
"The truth is that my only action in this case was that I denied a commutation," Huckabee said.
Huckabee acknowledged Tuesday that he initially favored DuMond's release but said he changed his mind when he realized commuting the sentence would mean the man would be under no parole supervision.
Huckabee dismissed any suggestion that he was able to twist the arms of the parole board.
"If I'm that persuasive that I can walk in, a new Republican governor, and persuade Clinton and Tucker appointees to do something that they didn't want to do - folks, I deserve to be president," he said.
Huckabee brought up the case in a gathering with reporters on the subject of his presidential campaign. Though not in the top tier of Republican candidates nationally, he has shown strength in leadoff Iowa.
He also said his fundraising has been improving.
Huckabee's Web site says he has raised more than $987,000 in online donations this month. He said he recently raised more money in a six-day period than he did the first three months of his campaign.
As of Sept. 30, Huckabee had raised $2.3 million and had $650,000 cash on hand. By comparison, Rudy Giuliani had $16.6 million cash on hand, Mitt Romney $9.2 million and Fred Thompson $7.1 million.
Huckabee has seen an increase in popularity among Iowa Republicans; he's now tied in second place with Rudy Giuliani at 13 percent, according to a University of Iowa Hawkeye poll out Monday. The poll had Romney leading with 36 percent.
"We feel like that a lot of things have turned," Huckabee said.