(CNN) -- Several potential Republican presidential contenders are heading to Las Vegas this week, hoping to hit the jackpot. And that's before they hit the casinos.
They hope the political payoff will come in appearances before some of the party's most influential donors attending the Republican Jewish Coalition annual spring meeting.
Former Florida Gov. Jeb Bush and current Govs. Chris Christie of New Jersey, Scott Walker of Wisconsin and John Kasich of Ohio will speak before the group, which seeks to promote Jewish causes among Republicans.
Many of the nation's leading Republican fundraisers and donors are part of the organization. Some donors estimate about a third of the party's most important fundraisers are active in the coalition, so it's a major audience for the possible presidential candidates attending.
Bush is getting a lot of attention because he has been tapped to speak at a private, VIP dinner with major financiers on Thursday night -- giving him top billing for the event and a major platform as he considers whether to seek the party's nomination. While he has said he won't make a decision until the end of this year and won't engage in further talk about the subject, Bush has recently picked up the pace with his political schedule, appearing in the past two weeks at fundraisers for Sen. Lamar Alexander, R-Tennessee, and Govs. Susana Martinez, R-New Mexico, and Brian Sandoval, R-Nevada, both running for re-election, as well as at an event for House Republicans helping him build a network of supporters if he needs one.
"Jeb has something to prove at this meeting," one influential Republican donor who will be attending told CNN. "It is pretty significant" for him to come to the event because he has refused to tip his hand any more about his intentions, the donor said. "Jeb has to do a good job of handling that issue."
Another party money man said the event is a "great opportunity for him" with decision-makers. "Showing up and speaking is showing 'I am taking this seriously,' " is how he put it to CNN.
Bush, who served as Florida's governor from 1999 to 2007, is liked by many in this key group. During his tenure, and his father's and brother's time in the White House, they built good relations with the American Jewish community.
Many eyes on Christie as well
Christie, who speaks on Saturday, is also known to many in this group.
"Most of the people will be making a judgment on Christie" during his appearance, one of the donors told CNN. "We are not absent 'Bridgegate,' " referring to the scandal over the closing of access lanes to the George Washington Bridge last year in an apparent act of political retaliation by some of his aides. Christie has said he was not aware of the closings until they happened.
"People are going to want to have the hallway conversations ... private meetings" to discuss where the controversy stands, the donor said.
A different major party fundraiser said that Christie so far has emerged fine among many of the donors, who like his political accomplishments and policies.
"I don't think in the long term this will harm him," the fundraiser said.
As Christie travels around the country raising millions as head of the Republican Governors Association, he is building up support among the donor class.
Besides their public appearances at the meeting, Christie, Kasich and Walker all can be expected to have smaller individual sessions with some influential attendees.
Will Adelson tip his hand?
The host for the weekend activities is Republican mega-donor Sheldon Adelson, owner of the Venetian Casino where the meeting is taking place, and active in the Republican Jewish Coalition. Adelson and his wife gave $93 million to various groups and candidates in the 2012 election cycle, according to the Center for Responsive Politics, making them the biggest individuals financiers of outside groups.
The Thursday dinner will be at the airport hangar Adelson uses.
While candidates and groups would love to have his support, several GOP donors said they doubt Adelson will tip his hand any time soon. One said he is "very hard to uncover ... he likes to support existing groups with real structure."
Adelson did support the super PAC Winning Our Future that backed former House Speaker Newt Gingrich in 2012 because of his pro-Israel stance, a majority priority for Adelson.
Besides Adelson, some of the more influential Republican fundraisers include businessman Lewis Eisenberg, former ambassador Sam Fox, former Republican National Committee Chairman Ken Mehlman, and former ambassador Mel Sembler.
All over the place
Unlike four years ago where most of these donors ended up supporting Mitt Romney, this go-around is expected to be much different.
"You still have the donor groups all over the place," said one of the fundraisers while also emphasizing just how early in this process things stand.
The amount of activity by the field of possible 2016 contenders reaching out to prospective financial backers is at about the same pace it was four years ago, several of those interviewed said. What is different, they said, is that the field at this stage appears to be shaping up to be much stronger than last time around -- meaning the battle for support among these key supporters will likely be intense.
"I think the difference is in the quality of the candidates," the fundraiser said.
CNN has learned Texas Gov. Rick Perry and Louisiana Gov. Bobby Jindal, who have been traveling the country as part of their official duties, met recently with some prominent Republican donors, but did not indicate their future plans.
One of the most active Republicans considering a White House bid has been Sen. Rand Paul of Kentucky, who has met with donors and who has been working to broaden his appeal beyond his father's libertarian base.