ABC News’ Emily Friedman and Arlette Saenz report:

ORLANDO, Fla. — Whether the booing happened at Thursday’s night’s debate is still a mystery to former Pennsylvania Sen. Rick Santorum.

Asked again about the booing after a question was posed to him by a gay soldier at the Fox News-Google Debate in Orlando, Fla.,   Santorum insisted that he “didn’t hear” the chants and isn’t even sure what audience members would be booing about.

“I didn’t hear it. I didn’t hear the boos,” Santorum told ABC News. “I heard the question and answered the question, so I’ve heard subsequently that happened. I’ve heard varied reports about whether they were booing the soldier or the policy.”

“I don’t know what they were booing,” he said. “If you can go out and find the people who were booing and find out if they were booing because a man was gay or because of a policy they don’t agree with.”

“You find out why they booed, and I’ll respond to your question,” he added.

But several other presidential candidates told ABC News that they did hear the boos ring through the Orange County Convention Center, chants that were spurred by a question gay soldier Stephen Hill asked about the “Don’t Ask, Don’t Tell” policy.

Hill asked, “In 2010, when I was deployed to Iraq, I had to lie about who I was, because I’m a gay soldier, and I didn’t want to lose my job,” said Stephen Hill, whose image was projected on a large TV screen in the debate hall. “My question is, under one of your presidencies, do you intend to circumvent the progress that’s been made for gay and lesbian soldiers in the military?”

Former Utah Gov. Jon Huntsman told ABC News that it was “totally unfortunate and unnecessary when someone in uniform asks a question of a panelist in this case, the first response should be thanking the soldier for his or her service.”

“We all wear the same uniform in America. We all salute the same flag I have two boys starting their journey in the U.S military. We should take more time to thank them for their services as opposed to finding differences based on background or orientation,” said Huntsman.

Former New Mexico Gov. Gary Johnson said he was embarrassed.

“That’s not the Republican Party that I belong to,” said Johnson. “I’m embarrassed by someone who serves in the military and can’t express their sexuality. I am representing the Republican Party that is tolerant. And to me that shows an intolerance that I’m not a part of in any way whatsoever. ”

Johnson added that he could hear the boos from the stage and believes that the other candidates – despite Santorum’s denial – could as well.

Businessman Herman Cain declined to go into detail about the incident saying only, “If you don’t have time to explain your whole position on that, you can very easily be taken out of context so I don’t even want to comment on that.”

Rep. Michele Bachmann’s spokeswoman Alice Stewart said in an email to ABC News, “There was booing and cheering throughout the debate – Michele didn’t comment on any of it.”

Former  House Speaker Newt Gingrich also declined to comment, and Ron Paul’s campaign did not immediately respond to a request for comment.

Spokespeople from Gov. Mitt Romney’s campaign did not return  requests for comment, and Texas Gov. Rick Perry’s campaign had no comment either.

ABC News’ Matt Jaffe, Susan Archer, Sarah Kunin and Jason Volack contributed to this report.