Sen. Marco Rubio (R-Fla.), shown here speaking at the Conservative Political Action Conference in February, is working to line up donors for a possible 2016 presidential run. (Kevin Lamarque/Reuters)

Jeb Bush’s success in rounding up GOP donors as he pursues a likely presidential run has created a big question for his fellow Floridian Marco Rubio: Will there be any money left for him?

That’s where Norman Braman comes in. The billionaire Miami auto dealer and longtime Rubio benefactor is expected to put as much as $10 million into a pro-Rubio super PAC if the senator decides to run, according to people familiar with his plans.

“If there is a super PAC that’s founded, I will give substantially,” Braman said in an interview, declining to be more specific.

“I don’t pay any attention to that other distinguished Floridian,” he added, referring to the former governor. “I respect Jeb Bush, but I think we need someone who represents the next generation.”

Support from Braman, a former owner of the Philadelphia Eagles football team, is exactly what the 43-year-old first-term senator needs. Rubio is expected to announce his presidential campaign next month, but he faces big hurdles as he prepares to do so. In a year when many donors are excited about governors such as Bush and Scott Walker of Wisconsin, his profile as a rookie senator with dazzling oratorical skills — similar to the Democratic incumbent in the White House — is a harder sell.

Sen. Marco Rubio (R-Fla.) urged the audience at the 2015 Conservative Political Action Conference to consider what must be done to ensure America remains "exceptional." (AP)

While Bush has been conquering the country’s money capitals with high-dollar fundraisers, Rubio has been on his own national tour, quietly expanding his financial base and reconnecting with donors he first met during his insurgent 2010 Senate campaign.

After confident performances at a January gathering of conservative donors in Rancho Mirage, Calif., and the recent Club for Growth conclave in Palm Beach, Fla., Rubio is winning over a small but wealthy group that sees him as a fresh party face willing to outline specific policy ideas, according to multiple GOP strategists and fundraisers.

“There are a number of people in a similar financial position that have indicated strongly that they will be supportive,” Braman said.

Among Rubio’s supporters is a cadre of donors who participate in the political network organized by industrialists Charles and David Koch, according to a person familiar with their thinking. Rubio has also been intensely courting casino magnate Sheldon Adelson. The two had a long one-on-one dinner Monday at a Washington steakhouse.

The backing of a handful of enormously rich financiers for an allied super PAC could help keep Rubio aloft in the competitive GOP primaries, much as Adelson did for former House speaker Newt Gingrich in 2012. Rubio advisers also say he has made enough inroads with the broader donor class to be able to raise significant funds for his own campaign operation — perhaps $40 million to $50 million by next year’s Iowa caucuses.

“I don’t think Marco is going to hurt for money at all,” said Scott Weaver, who heads the public-policy practice at the Washington law firm Wiley Rein and is helping spearhead Rubio’s fundraising efforts.

Rubio also has the financial support of Wayne Berman, who served as national finance chairman for Sen. John McCain’s 2008 GOP presidential campaign and was a top adviser to Mitt Romney’s 2012 campaign.

Rubio advisers say he does not need to match Bush’s massive fundraising apparatus, which is expected to bring in as much as $100 million by early spring. The plan is to run a lean operation, begin visiting early-primary states and get to the first debate in August — visits and stage performances that they argue will help tilt the momentum in his favor.

The senator is widely regarded as one of the party’s best communicators — something that has helped him win over donors in one sitting.

“I’ve been at events this year where people will come in and have a notion of who they will likely support, and by the time they spend an hour with Marco, they say: ‘I’m in. What can I do?’ ” Weaver said.

In the coming weeks, Rubio will work to cram in as much face time with major donors across the country as possible. His next stop is an appearance Friday at an American Enterprise Institute conference, at a luxury resort on Georgia’s Sea Island, that will be attended by some of the biggest givers on the right. After that, Rubio is scheduled to meet with a group of top chief executives in Manhattan early next week.

But the aggressive travel schedule has contributed to Rubio’s distinction as the most absent senator. He has missed 8.3 percent of Senate votes since joining the body in 2011, according to GovTrack, a nonpartisan group that catalogues government activity.

George Seay, a Dallas-based investment manager, said he first met Rubio during his 2010 Senate campaign at a meeting of the Legacy Political Fund, an organization of conservative business and civic leaders whose former members include Sens. Ted Cruz (R-Tex.) and Steve Daines (R-Mont.).

After that session, Seay said he concluded that Rubio “would be likely to be successful at the presidential level and would be outstanding in the position.”

At the Club for Growth gathering in Palm Beach last week, Rubio impressed the crowd with his compelling biography as the son of Cuban immigrants and how he handled domestic and foreign policy questions.

“I measure candidates on three issues: Can their policies grow our economy? Can their policies protect us culturally? Can their policies protect us physically?” said New York venture capitalist Ken Abramowitz, who was among those in attendance. “He got an A each time. I walked him to his car and I congratulated him.”

Still, Abramowitz said he is still “in the learning phase.” Among the potential candidates he views as most compelling right now — along with Rubio — are Bush, Walker and Cruz.

While much of the money in his home state has gravitated to Bush, Rubio still has the potential to raise large sums, some GOP fundraisers say.

“The vast majority of the significant donor community has signed on with Jeb, and my guess is that’s going to hold true throughout the campaign,” said Tallahassee lobbyist Brian Ballard, a top Bush fundraiser. “But Florida is a big state with a lot of wealthy folks who I’m sure find Marco’s appeal very compelling. I could see him still doing well in Florida.”

But Mac Stipanovich, another veteran Tallahassee operative, said Rubio would struggle to find financial support in Florida. “I don’t know anyone in Republican circles in this state who isn’t with Bush for president,” he said in a recent interview.

Stipanovich said he recently conducted a marketing research poll for a private-sector client that found Florida Republicans preferred Bush, followed by Walker second and Rubio in third place.

Rubio’s most valuable financial backer is Braman, who sells Audi, BMW, Porsche and Rolls Royce vehicles at dealerships in Florida. He first met Rubio when he was a state legislator on the verge of becoming Florida House speaker.

Braman — estimated by Forbes to be worth $1.9 billion — said he walked away from the meeting convinced that “this is an extremely intelligent, bright young man.” He became a donor, benefactor and family friend, traveling with Rubio to Israel at one point. Rubio’s wife, Jeanette, works part time at Braman’s family foundation.

When Rubio left Tallahassee for Washington, the Miami businessman was among those featured in a tribute video for him. On camera, Braman predicted that Rubio someday would be president.

“I haven’t changed my opinion,” he said.