Who will win "the Sheldon primary"? GOP hopefuls head to Vegas

Many of the top Republican presidential contenders will be vying Thursday night for the support of one mega-donor: billionaire Sheldon Adelson, the world's ninth-richest person, according to Forbes magazine.

However, when it comes to politics, he has a history of backing candidates who do not win. As the hopefuls converge in Las Vegas, the casino magnate has a new strategy to change his luck, CBS News' Jan Crawford reports.

The Republican governors are heading west to Las Vegas. New Jersey's Chris Christie, Ohio's John Kasich, Wisconsin's Scott Walker and former Florida Gov. Jeb Bush are speaking at the spring meeting of the Republican Jewish Coalition. But more important at that event is holding private talks with Adelson.

Former George W. Bush press secretary Ari Fleischer serves on the coalition's board and has known Adelson for almost a decade.

"I call it the Sheldon primary," Fleischer said. "I think that every candidate who is coming to Las Vegas has already asked for one-on-one time with Sheldon. He can be extraordinarily influential. Sheldon can keep a candidacy alive, or he can take out somebody else's candidacy."

That certainly was the case in 2012, when Adelson funneled $15 million into a Newt Gingrich super PAC, helping pay for tough ads targeting the front-runner, Mitt Romney.

Adelson's support kept Gingrich around longer than anyone expected. His attacks left Romney bruised and battered going into the general election.

Eric Fehrnstrom, a top Romney adviser, said, "Sheldon Adelson was a good friend to Mitt Romney in the latter stages of that campaign, but I think he felt a particular devotion to Newt Gingrich. He felt he had to support Newt, and it was that support that kept Gingrich alive past his normal expiration date."

After Gingrich bowed out, Adelson changed his tune, giving $20 million to pro-Romney groups.

In total, Adelson and his wife gave more than $92 million of their personal fortune to conservative candidates in the 2012 race.

But the billionaire businessman, who made a fortune with casinos, often backed the wrong horse. Most of his candidates lost.

This time, he's changing his approach, relying less on who he likes and more on who can win. And, Crawford added, the possible contenders descending on Vegas will be making the case to Adelson that they fit that bill.

Adelson rarely speaks publicly. CBS News made several requests for an interview, but his representatives declined.