Rick Santorum on Wednesday said President Barack Obama and Mitt Romney have not fought the battle against gay marriage, unlike himself.

Santorum made his remarks during a campaign stop in South Carolina, which will hold its presidential primary on Saturday.

When asked, “What would you do as president to ensure that marriage remains between a man and a woman? And could you contrast your position to those of the other candidates,” Santorum, a former senator from Pennsylvania, questioned Romney's and Obama's opposition to marriage equality.

“I was one of the authors of the federal marriage amendment and when it was originally drafted I had been out there sounding the alarm on what the Supreme Court was going to do and what other courts were going to do. … And there isn't usually a day that goes past that I'm not attacked in some place for standing up – more than anybody else.”

“You want to contrast it; I've fought the battle,” Santorum added. “It's one thing to say, 'I support it,' and it is another thing to actually go out and fight the battle.”

“President Obama says he supports traditional marriage, but does he have any evidence that he's actually doing anything to … in fact, everything he's doing is trying to undermine it.”

“Look at Governor Romney, when he was in Massachusetts. Look at the people he appointed to the court who undermine the privilege of marriage between a man and a woman.” (The video is embedded in the right panel of this page. Visit our video library for more videos.)