Jeb Bush speaks to senior citizens in Las Vegas on Monday. (Steve Marcus/AP)

An unusual request has gone out to wealthy donors writing large checks to support former Florida governor Jeb Bush: Please don’t give more than $1 million right away.

The requested limit, confirmed by multiple people familiar with the amount, may mark the first time that a presidential hopeful has sought to hold off supporters from contributing too much money.

The move reflects concerns among Bush advisers that accepting massive sums from a handful of uber-rich supporters could fuel a perception that the former governor is in their debt. The effort is also driven by a desire to build as broad a pool of donors as possible among wealthier contributors.

So even as Bush (R) is headlining a series of high-dollar events for a super PAC backing his bid, fundraisers have been instructed not to ask donors to give more than $1 million per person this quarter.

“This campaign is about much more than money,” said Howard Leach, a veteran Republican fundraiser who recently co-hosted a finance event for Bush in Palm Beach, Fla., and confirmed the limit. “They need substantial funds, but they don’t want the focus to be on money.”

Bush spokeswoman Kristy Campbell declined to comment.

The perceived need to put limits in place for contributions, even if only for a few months, underscores the extraordinary role that elite financiers play in political fundraising, which increasingly centers on super PACs able to collect unlimited sums from individuals and corporations. The move reflects the sensitive challenge facing candidates who want to tap into those resources­ without relinquishing their claims of independence.

Bush has yet to officially declare his candidacy, but he is already on track to raise tens of millions of dollars by the end of this month for two political action committees, both named Right to Rise, that were set up in January. His potential rivals have acknowledged that they have little hope of matching his pace.

Pro-Bush fundraisers have been encouraged to stick to the $1 million-per-donor limit for the first 100 days. Of course, many donors who give large amounts now are likely to be repeat givers — and write even larger checks — once the campaign starts in earnest.

Bush is entering his third month of an intensive, cross-country fundraising tour that has included stops at lavish Manhattan apartments, premier Washington lobbying shops and luxury hotels in Florida.

During a stop in Las Vegas this week, Bush had a private meeting with casino mogul Steve Wynn. On Tuesday, he headlined an evening reception for the Right to Rise super PAC at the Sanctuary Camelback Mountain Resort, just outside Scottsdale, Ariz. Among the fundraiser’s co-hosts was former vice president Dan Quayle.

Amid the nonstop drive for money, Bush advisers are cautioning fundraisers in conference calls and in-person discussions not to allow a few mega-donors to overwhelm the effort.

“It shows they are disciplined and appreciate that the dominance of a few key people early on is not a productive thing for the campaign or for Jeb Bush,” said Rick Hohlt, a longtime Republican fundraiser in Washington who is familiar with the guidance.

Such a dynamic dogged the 2012 campaign of former House speaker Newt Gingrich, whose bid for the Republican nomination was lifted by a super PAC financed with $15 million from casino magnate Sheldon Adelson and his family. When former senator Rick Santorum of Pennsylvania ran, his super PAC benefactor was investor Foster Friess.

Bush is tapping into a much wider pool of wealthy donors. Dozens of backers have given $100,000 each to get into high-end super PAC fundraisers, such as one last month at the Park Avenue home of private-equity titan Henry Kravis.

And some are offering substantially more than that.

Leach — who served as ambassador to France during the administration of George W. Bush — said he knows of “numerous” people across the country who have already given $1 million.

“They didn’t need to be persuaded,” he said. “The reason people are willing to write checks like that is because they feel this election is so important to the future of this country.”

Among those donating large amounts, Leach said, are Democrats disenchanted with former secretary of state Hillary Rodham Clinton, who is nearing her own bid for the 2016 presidential race.

The eagerness among political financiers to support Jeb Bush is evident in the high goals his team has laid out for donors and fundraisers to reach by March 31, with tiers set at $50,000, $100,000, $250,000 and $500,000, according to people involved in collecting checks.

Bush’s rapid fundraising clip puts his super PAC on pace to far outstrip Restore Our Future, a super PAC that backed 2012 Republican presidential nominee Mitt Romney and raised $12 million in its first six months.

In the coming weeks, Bush is scheduled to headline additional fundraisers in Denver; Sea Island, Ga.; Boca Raton, Fla.; and Atlanta. There, the cost of co-hosting a one-hour breakfast at the city’s elite Capital City Club has been set at $25,000 a person.

Ed O’Keefe contributed to this report.