Vice President Joe BidenJoe BidenTop union offers backing for Ellison in DNC race John Kerry to teach at Yale on global issues Ellison needles Perez for 'unverifiable' claim of DNC support MORE and Sen. Ted CruzTed CruzTrump to interview four candidates for national security adviser Milo Yiannopoulos to speak at CPAC Reports: Petraeus off the list, Trump down to three candidates to replace Flynn MORE (R-Texas) headlined dueling fundraisers just two miles apart Friday night in South Carolina, in what could be an early preview of the 2016 race for the White House.

Biden, who was looking to build support for Elizabeth Colbert Busch, the Democratic nominee in next week's special congressional election, acknowledged his visit was likely to prompt speculation.

“[Rep.] Jim [Clyburn] called me and asked me if I'd be willing to do this, and I said, ‘Jim, you know I love going to South Carolina, but as soon as I show up in South Carolina, there will be Washington press coming down, saying is Biden getting ready?’” Biden said. “I’ve got to make clear: I would go anywhere Jim asked me to go.”

Presidential hopefuls frequently make visits early and often to states like South Carolina, Iowa, and New Hampshire that vote early in the presidential primaries, giving them outsized influence on the nominating process. But aside from his brief acknowledgment of the speculation, Biden stuck to praising Colbert Busch and providing red meat for Democratic donors.

“It's particularly good to be back in South Carolina, knowing you're about to get another Democratic congressional seat in the First District," Biden said. "All you had to do was watch that debate to understand why Elizabeth is going to make such a great congresswoman. They ain’t seen nothing yet.”

He also blasted Republicans for an economic policy he argued only benefited the very wealthy.

"One of the things that bothers me most about the new Republican party is how down on America they are, how down on our prospects they are, how they talk about how we're getting clobbered, how they talk about things that have no relationship to reality, all in the name of making sure that the very few at the top do very well," Biden said.

Down the road, Cruz returned fire, taking a shot at Biden's reputation for gaffes.

"So Vice President Joe Biden's in town," he said. "You know the great thing is, you don't even need a punch line. You just say that and people laugh."

Earlier this week, the National Review reported that the freshman senator was weighing a 2016 presidential bid at the urging of grassroots supporters in the party. But in a post to his Facebook account, Cruz said his focus remained on the Senate.

"It is a continued source of amazement that the simple fact that I am working hard with like-minded Senators to keep my promise is seen as newsworthy and cause for wild speculation," Cruz wrote.

But Cruz's attendance at the dinner — and request that supporters share their contact information with his political action committee via text message — will only add fuel to that fire.

In his speech, Cruz declared that "our freedom is in jeopardy in this country" and accused the Obama administration of recognizing "no limits on its powers." He also told the party faithful they should not be "demoralized" by last year's election, noting that it was less than a decade ago that Republicans controlled both chambers of Congress and the White House.

"Things can change quickly," Cruz said. "I believe change will come quickly."