Before Iowa and New Hampshire, GOP candidates are competing in the Sheldon Adelson primary, and some will travel to his posh Venetian hotel in Las Vegas this weekend in hopes of winning it. But one candidate — Marco Rubio — has emerged as the clear front-runner, according to nearly a half-dozen sources close to the multibillionaire casino mogul.

In recent weeks, Adelson, who spent $100 million on the 2012 campaign and could easily match that figure in 2016, has told friends that he views the Florida senator, whose hawkish defense views and unwavering support for Israel align with his own, as a fresh face who is “the future of the Republican Party.” He has also said that Rubio’s Cuban heritage and youth would give the party a strong opportunity to expand its brand and win the White House.

Winning the backing of the 81-year-old Adelson would give Rubio a serious boost in his quest for the 2016 Republican nomination. His campaign is predicated on the idea that he can appeal to a broad swath of primary voters and stay in the race long enough to outlast well-funded establishment favorites like former Florida Gov. Jeb Bush and Wisconsin Gov. Scott Walker. To do so, he’ll need the support of deep-pocketed contributors like Adelson, whose $32 billion net worth makes him the nation’s 12th-richest person, according to Forbes.

In 2012, Adelson’s financial support allowed former House Speaker Newt Gingrich to stay in the presidential race long after other donors gave up on him.

Adelson’s attraction to Rubio is in no small part centered on the Florida senator’s outspoken support for Israel, an issue near and dear to the billionaire’s heart. Rubio has reached out to Adelson more often than any other 2016 candidate, sources close to Adelson say, and has provided him with the most detailed plan for how he’d manage America’s foreign policy.

Since entering the Senate in 2011, Rubio has met privately with the mogul on a half-dozen occasions. In recent months, he‘s been calling Adelson about once every two weeks, providing him with meticulous updates on his nascent campaign. During a recent trip to New York City, Rubio took time out of his busy schedule to speak by phone with the megadonor.

The connection is also personal. Adelson, whose father emigrated from Lithuania and worked as a cab driver, has come to admire Rubio, the son of a bartender and a hotel maid, for his compelling life story. On March 2, the two had a private dinner at Charlie Palmer, a posh steakhouse at the foot of Capitol Hill. There, they talked for hours about their families and personal lives. “It lasted quite a while,” said one source close to Rubio.

Alex Conant, a Rubio spokesman, declined to comment on the outreach to Adelson. “We don’t discuss private meetings,” he said.

Adelson has yet to declare his support for a 2016 candidate, and those familiar with his political views stress that he could ultimately get behind a candidate other than the Florida senator. But he’s also provided subtle public hints about his leanings. On April 7, two Florida-based Adelson lobbyists, Scott Ross and Nick Iarossi, headlined a Rubio breakfast fundraiser in Tallahassee.

Andy Abboud, an Adelson spokesman who doubles as his political gatekeeper, wouldn’t comment on the Rubio discussions other than to say: “It’s a wide-open field and he’s going to keep his powder dry until he needs to weigh in. He’s excited about the field of candidates.”

Should he make an endorsement, Adelson’s advisers say, he would not do so until after the second Republican primary debate, which is expected be held at the Ronald Reagan Presidential Library in Simi Valley, California, in September. But he’s already playing a public role in the 2016 sweepstakes. This weekend, at his Venetian hotel, Adelson will preside over the Republican Jewish Coalition’s spring meeting, a key cattle call for presidential aspirants.

In attendance will be a group of well-heeled Jewish Republican donors, many of whom see Adelson, who serves on the RJC’s board of directors, as a leader. Ari Fleischer, who was a press secretary in the George W. Bush White House and is also active with the group, said most people in the coalition supported either Bush, Walker or Rubio.

“I think there are many people at the RJC who are going to be influential in the primary,” he said. “A lot of the people who aren’t behind a candidate yet, including me, are shopping.”

During the 2012 campaign, Adelson made his voice heard loud and clear. Of the $100 million he spent on Republican causes, about $15 million was devoted to supporting Gingrich, his favored candidate in the primary. His benevolence enabled the former House speaker, who was waging a long-shot campaign, to remain in the primary until late April.

This election, though, Adelson’s advisers say he’s determined to get behind a more mainstream candidate who has a better chance of becoming the party’s nominee. “He doesn’t want the crazies to drive the party’s prospects into the ground,” said one person close to him.

He’s held private meetings with most of the Republican candidates, many of whom have courted him with fervor. But he’s become particularly fond of Rubio, who attended last year’s RJC meeting but who will not be present this year. He has told some friends that the senator would offer the party a freshness that most other contenders, including Bush, cannot.

In private, Adelson, who’s had labor disputes with workers at his Venetian property, has also said positive words about Walker and that he admired how Wisconsin governor handled his 2011 clash with organized labor.

But Adelson’s desire to get behind an electable candidate may also mean that others with whom he has close ties will be left by the wayside. Texas Sen. Ted Cruz, who shares many of Adelson’s foreign policy views, and South Carolina Sen. Lindsey Graham, who last year sponsored an anti-Internet gambling bill that the casino magnate supported, will be appearing at the RJC confab on Saturday in hopes of winning the mogul’s support.

But, Adelson’s advisers say, there remain questions about whether either will be able to establish the kind of broad national following that would be needed to win the presidency.

For another 2016 hopeful, Kentucky Sen. Rand Paul, it’s not about winning Adelson’s endorsement — it’s about making sure he doesn’t come after him.

During an appearance on a Jewish-themed radio program last month, Paul, who’s come under fire from the neoconservative wing of his party for his more isolationist foreign policy views, said he’d recently had a private meeting with Adelson and his wife, Miriam, and asked him about a report that he was considering funding a campaign against him.

“They assured me there was no truth to that,” Paul said.

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