Former Florida Governor Jeb Bush and U.S. Sen. Marco Rubio grew up, politically, in the same power circles in Miami. The two men share many of the same Republican donors and friends who helped them ascend South Florida’s bare-knuckles political world.

But now, with the ever-growing possibility of a showdown between Bush and Rubio for the GOP’s 2016 presidential nomination, the political powerbrokers and donors who count both candidates as friends may soon have to pick a side.

At the moment, Bush appears to have a slight edge.

George LeMieux, a Fort Lauderdale attorney who served as interim U.S. senator between August 2009 and December 2010 after Mel Martinez resigned, told Fox News Latino that he is actively involved in organizing fundraising events for Bush’s exploratory political action committee, Right to Rise.

“Gov. Bush is asking all his friends and supporters, including myself, to support his efforts,” LeMieux said. “I am working on a number of events for him throughout Florida. Everyone I know is getting on board.”

He also said that Rubio has not informed him or other top Republican donors in the state that is planning a presidential campaign.

“The money Sen. Rubio is raising right now is for his senate run, as far as I know,” LeMieux said.

Nelson Diaz, chairman of the Miami-Dade Republican Party, echoed LeMieux. “Until Marco comes out and says he is running for president, people are assuming he is running for re-election,” Diaz said. “Although I know some folks who will support both of them and some folks who really hope Marco runs for president.”

The senator is certainly making the type of moves that normally precede a presidential run. Anna Rogers, the former finance director for Karl Rove’s American Crossroads PAC, has taken on a similar position with Rubio’s PAC, Reclaim America. According to press reports, Rubio has instructed his top aides to prepare for a presidential campaign.

After entertaining 300 supporters and donors at a summit about his political future, Rubio skipped out on his Senate duties in order to raise money in California, Texas and Chicago and squeezing in book tour stops in early primary states such as Iowa, New Hampshire, South Carolina, Florida and Nevada.

In December, Rubio said that whether or not Bush entered the presidential fray would not influence his decision.

“It is not unusual in presidential campaigns for people who have worked together in the past to end up running at the same time," Rubio told NPR. "If I join the field, if Gov. Bush joins the field and others join the field, you could have as many as eight to 10 very credible candidates running. And there's nothing personal. I wouldn't be running because I'm against anybody else in the field. I would be running because I believe I have something unique to contribute at this time."

Meanwhile Charlie Spies, the Republican election law lawyer who ran the 2012 PAC that spent $156 million on Mitt Romney's presidential run, has signed on to team Bush. Spies registered both Bush’s leadership PAC and his “Right to Rise” PAC.

Coincidentally or not, Bush had a secret powwow with Romney in Utah just days before the former Massachusetts governor announced he would not make a third bid for the White House.

In addition to LeMieux and other established Republican players in Florida, like former state GOP party chairman Al Cardenas and real estate developer Armando Codina, Bush also enjoys the backing of young, rising stars in the campaign fundraising circuit.

Luis Andres Gazitua, a Miami lawyer who is close friends with Bush’s sons George P. and Jeb Jr., is part of a group organizing a Coral Gables fundraising party in March for a Texas super PAC founded by the two siblings.

“Miami is a small town,” Gazitua said. “There are significant long-term personal and familial relationships between these potential candidates and donors. Therefore, an opposing candidate can’t expect a donor not to support a long-term friend."

Others, like Diaz, who is a close friend of Rubio, would prefer to remain neutral. “Quite honestly I feel comfortable with either guy being our nominee,” he said. “It puts Florida and Miami in a real unique position.”