Marco Rubio speaks during a campaign town hall at Barefoot Resort in North Myrtle Beach, S.C., on Feb. 16, 2016. (Chris Keane/Reuters)

NORTH MYRTLE BEACH, S.C. -- Sen. Marco Rubio (R-Fla.) responded to a man who shouted "Waterboard Hillary!" at a presidential campaign event Tuesday by appearing to jokingly suggest that he didn't hear what was said and laughing off the remark.

The exchange came after Rubio, who has advocated the continued use of the Guantanamo Bay detention facility in Cuba, reiterated his call: "This is a message to the Cuban government and anyone who’s listening: We’re keeping Guantanamo -- forever," he said to cheers. "We’re keeping it forever. It’s a good base."

Then, a man yelled out: "Waterboard Hillary!" a clear reference to Democratic presidential candidate Hillary Clinton.

Many in the crowd quickly reacted to his comment with a laugh. Rubio appeared to laugh it off as well.

"I don’t want to know what he said," responded Rubio, adding: "The press is here, I didn’t even hear what they — I didn’t hear what they said. I know it wasn’t a bad word, that’s all that matters."

Politicians have come under criticism for not rebuking controversial comments by supporters. At a rally last year, for example, Donald Trump did not challenge an audience member who said that President Obama is Muslim and "not even an American."