One person involved with the party took to Twitter, asking: "Have you people lost your minds?" Another joked: "Aren't YRs a lil' old for him?"
This was the same guy who resigned just before the 2006 election over salacious e-mails to former male congressional pages.
For Foley, though, it offered an opportunity to get back in front of a GOP audience for the first time since he went into hiding.
His speech got applause, not jeers. And now he's the host of a political talk show on a local radio station.
"He was amazing. Charismatic. He has a great message and touched on so many different things and seamlessly did it," said Jackie Fay, the group's president who asked him to speak. "He's enthralling to listen to."
After a self-imposed seclusion, Foley is back in the public eye and earning respect in the community he represented in Congress for almost 12 years. He has a radio show on politics. Many in the community encouraged him to run for mayor in West Palm Beach, though he ruled it out. He returned to public speaking, addressing a Jewish veterans group two days before the Young Republicans.
"It's a happy ending," he said. "It is gratifying. Believe me."
Not that everyone has forgiven him. When the idea of Foley running for mayor hit the news, the comments on blogs and news websites were brutal.
And when Fay used Twitter to announce Foley was going to speak to her group, which is open to Republicans aged 18 to 40, the critics spoke up.
"Can I know why (at)PBCYR seems to be excited about Mark Foley being their guest spkr? Have you people lost your minds?" tweeted Brandi Brown, a Tallahassee events planner who has worked for Republican politicians.
Then there were the jokes. "Aren't YRs a lil' old for him?" tweeted Apryl Marie Fogel, who works for a group that promotes conservative fiscal policies.
Fay said she never reconsidered the invitation and dismissed the barbs.
"It seemed petty and high schoolish. It was like, 'Oh! How could you do that?' Well, he's a registered Republican last time I checked. He served in office and he did a lot of good. And he's got years of experience to draw from," she said.
Foley readily admits his contact with former pages was wrong.
"It was horrific judgment," Foley said. "I'm going to punish myself for the rest of my life. People don't have to help."
While he was in rehab at an Arizona facility after he resigned, Foley said he was asked where he was going to live. People assumed that if he knew what was being written about him, he wouldn't go home to South Florida.
Foley jokes that as a congressman he would have attended the opening of an envelope. He was always accessible to the media and his constituents, often answering his Washington office phone himself.
That changed when he got home. He stayed in the house. He stopped returning reporters' phone calls.
"Press people throwing notes over the fences to see if I'd speak to them - very surreal," Foley said. "Someone who was so available to a camera, finding himself saying, 'No thanks, not now.'"
Also gone were his days socializing in Palm Beach restaurants. He began driving greater distances to shop at grocery stores where people were less likely to know him.
"I owned restaurants. I'm a cook, so I repracticed my brand, my trade. I would do a lot of reading, a lot of walking on the beach with my dogs. It wasn't the life I was used to, but it was a life that at least allowed me that time to heal," Foley said.
Foley's venture back into public began when a friend insisted they go out to dinner. He quietly went to his table instead of working the room like he used to. Then people approached him and wished him well.
"What I found in this reawakening or re-emergence, it's been a loving public. Remarkably so," Foley said.
Even some former constituents who were outraged by his conduct see the opportunity for a second chance.
"I was mad. I was really, really mad," said John Lloyd, 35, of West Palm Beach.
But Lloyd is among those that wanted Foley to run for mayor, saying he did a lot of good for the community.
"Hindsight's 20/20," Lloyd said after the Young Republicans meeting. "I hope people will open up their eyes and forgive him."
People didn't forget his level of community involvement, said Brian Crowley, a former Palm Beach Post political reporter who writes the "Crowley Political Report" blog and is a political analyst for a public relations firm.
"It just shows sort of the residual fondness for not only Mark but the whole Foley family," Crowley said. "People are willing, on a level, to give someone a second chance. In his particular case, the only thing that happened was the e-mail messages, and if it had gone further than that, I think it would have been less forgiving."
In 2009, Foley was offered a political talk show on WSVU-AM. He admits he was apprehensive about accepting, saying he wasn't sure if there would be picketers or hate calls. But he said it's been nothing but positive.
Foley was in the studio recently asking callers what they hoped President Barack Obama would say during the State of the Union address. A caller named Michael said the only thing that would make him happy would be to hear Obama say, "I resign."
"I'll put you in the anybody-but-Obama camp," Foley laughed.
"Mark, if you've got the itch, we'll hold up the signs for you," the caller said.
While Foley for president is a huge stretch, Foley for mayor wasn't.
"If he had run for mayor of West Palm Beach, he would have won. I have no doubt about that," Crowley said.
So why didn't he?
"My mother is still alive. My family, my sisters, my partner, they'd all lived the drama," Foley said. "I'm not certain that they need to be put through the wringer on my behalf or for my political ambitions again."