Then-Republican presidential candidate George W. Bush and his brother Jeb Bush, en route to a campaign event during the 2000 presidential race. (Eric Draper/AP)

LAS VEGAS — Former president George W. Bush plans to stay off the 2016 campaign trail as his younger brother prepares to mount a presidential bid, telling a group of Republican Jewish donors here that he does not want to fuel an anti-dynastic backlash.

At a closed-door dinner Saturday night before nearly 800 members of the Republican Jewish Coalition, the 43rd president noted that it could hurt former Florida governor Jeb Bush if he campaigned alongside another Bush who served in the White House, according to several attendees.

“He said that one of the challenges his brother is going to have is that the country doesn’t like dynasties,” recalled David Volosov, a RJC member from Silver Spring, Md. “People are going to say, ‘Oh, here comes another Bush.’ His response is that he is going to stay as far as way as he can. He is going to stay away from the whole process.”

“He basically said that his brother is going to have some issues with the name 'Bush' to contend with,” said Lisa Karlovsky of Scottsdale, Ariz.

Bush's comments were first reported by the New York Times.

For his part, Jeb Bush didn't dispute his brother's analysis when asked after a lunchtime meeting with two supporters in Miami Beach on Sunday.

"I think my brother overstates this a lot. People respect him enormously," he told reporters awaiting him outside a Burger & Beer joint.

But if he launches a formal presidential campaign, Jeb Bush said, "I’m going to have to show my heart, show my life experience. I can’t be about any kind of dynastic considerations." He added later that his brother is "smart enough to know that he needs to pull back a little bit, but that’s what he’s done in his post-presidency. That’s why he’s been admired by so many people. He doesn’t have an opinion about everything. He’s let this president have his successes and his mistakes, which is, I think, what former presidents need to be doing."

In Las Vegas on Saturday night, the former president largely deflected questions about Hillary Rodham Clinton, the likely Democratic presidential nominee, except to say that she would be a formidable opponent for the eventual GOP nominee.

“He said the Republican Party can’t underestimate her,” Volosov recalled.

Bush’s appearance capped a three-day leadership meeting of the Republican Jewish Coalition, a powerhouse fundraising group. Among the members of its heavyweight board is billionaire Sheldon Adelson, who hosted the gathering in his ornate Venetian hotel, on the Las Vegas strip.

Adelson kept a low profile during the brief portion of the meeting open to the media Saturday but hosted top donors for an alfresco opening dinner outside his mansion Thursday evening and was on hand for private addresses by top GOP leaders, including George W. Bush and House Speaker John Boehner.

Seated on a couch Saturday night in a ballroom of the Venetian, Bush delivered off-the-cuff, often-wry reminiscences about his presidency and his life since leaving the White House, queried by former aides Ari Fleischer and Josh Bolten. Bush steered clear of explicit criticisms of President Obama, stressing his respect for the institution.

“He was very careful not to criticize the administration,” said Tali Raphaely of Miami.

“He wasn’t scripted, he was just speaking from the heart, which is so refreshing,” Karolvsky said, “and he was very respectful of the current president.”

But Bush warned that the United States should not lift sanctions on Iran until its nuclear program is dismantled, suggesting that he has reservations about the current nuclear framework agreement.

“He said it’s absurd to think you can eliminate certain sanctions and then snap it back, that once you get rid of certain sanctions, they are gone forever,” said one attendee, who spoke on the condition of anonymity to describe the closed-door session.

Opposition to the framework agreement was the central topic of conversation at the RJC meeting. The organization has seen a burst of donations in recent months, spurred by anger on the right about Obama's approach to Iran and his fraught relationship with Israeli Prime Minister Benjamin Netanyahu.

Ed O'Keefe in Miami contributed to this report.

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