Jeb Bush’s advocacy group, by housing aides-to-be, is playing a more expansive role than previously known. (AP Photo/Brennan Linsley, File) (Brennan Linsley/AP)

A nonprofit group allied with former Florida governor Jeb Bush is playing a more expansive role in his current political operation than previously known, housing several top policy advisers who are expected to join his eventual campaign, according to people familiar with the structure.

At least four people with expertise on energy issues, foreign affairs and communications are working with Right to Rise Policy Solutions, a nonprofit advocacy group that can accept secret, unlimited donations from individuals and corporations.

Bush’s reliance on the non­profit as he prepares for a likely presidential bid puts him on untested legal ground, cloaking who is paying the salaries of his expected advisers. But a polarized Federal Election Commission is unlikely to scrutinize the maneuver, campaign finance experts said.

The latest hire was announced Monday: Michael Steel, a top spokesman for House Speaker John A. Boehner (R-Ohio), said that he was moving to Florida to take a role with the nonprofit group. If Bush officially launches a presidential campaign, Steel would join it, according to people familiar with the plans who were not authorized to speak publicly.

At least three others working for the group are expected to make similar moves. Marcus Peacock, a former staffer with the Senate Budget Committee, is working with the group on environmental and energy issues. Former congressional staffers Robert S. Karem and John ­Noonan are advising the former governor on foreign policy issues as paid consultants to Right to Rise Policy Solutions.

In a statement, William Simon, the group’s founder, said that if Bush launches a campaign, his entity “will continue its education efforts independent of such campaign.” He confirmed in a separate e-mail that “some of our policy team are on short-term contracts to help get up to speed building policy and creating an informational Web site. As the year progresses I expect that some will move on to other opportunities.”

Simon is a former Wal-Mart executive and was head of Florida’s Department of Management Services during Bush’s second term as governor. In February, Simon established Right to Rise Policy Solutions as a nonprofit corporation in his home state of Arkansas.

Having Simon’s nonprofit group temporarily house a team of Bush aides means that the public may never know who is paying the salaries of those helping craft Bush’s policies right now. Tax-exempt “social welfare” groups such as Right to Rise Policy Solutions can accept unlimited funds from individuals and corporations and are allowed to keep the names of the contributors secret. Simon has said he may end up disclosing the donors to the group, but it is unclear when that might happen.

“The beauty of nonprofits from the standpoint of some donors is that the source of the money will never see the light of day,” said Kenneth Gross, who heads the political law practice at Skadden Arps. “The entire process is going to be even less transparent than it has been in the past.”

Campaign finance experts said the nonprofit’s relationship with Bush is legally risky. A landmark 2002 law bans a candidate from directly or indirectly establishing an organization that is not subject to federal contribution limits.

It is unclear, however, how that would apply to Bush, since he has not yet declared his candidacy for the White House. And the FEC is mired in intense partisan gridlock, making it unlikely that the six-member panel would agree to pursue the issue.

“It seems to me that it is pushing the envelope, but I don’t know whether the FEC is going to take any action,” said Gross, a former associate general counsel at the commission.

Advocates for tougher enforcement of campaign finance rules said that Bush’s aggressive use of a nonprofit in his political operation undermines the federal contribution limits, which permit individuals to give up to $2,700 to a candidate per election. The former governor has also been raising money at an intense clip for his allied super PAC, also called Right to Rise.

“This is another example of how he is running roughshod over campaign finance law,” said Larry Noble, senior counsel at the Campaign Legal Center. “He is outsourcing what will normally be campaign activity, and he’s not even admitting he’s testing the waters, which is absurd.”

Kristy Campbell, a spokeswoman for Bush, said in an e-mail Monday that his team is “fully complying with the law in all activities Governor Bush is engaging in on the political front and will continue to do so.”

Bush is not the first presidential contender to have an allied tax-exempt organization. A super PAC set up to back President Obama in 2012 had a smaller nonprofit arm, Priorities USA, which ended up giving most of its money away to groups such as Planned Parenthood and Hurricane Sandy relief efforts before being dissolved, according to tax documents.

Other 2016 Republican contenders — including Sen. Marco Rubio of Florida, former Arkansas governor Mike Huckabee, former Texas governor Rick Perry, Louisiana Gov. Bobby Jindal and former senator Rick Santorum of Pennsylvania — have aligned nonprofits groups that have conducted polling, developed policy and covered travel expenses.

But Bush’s advisers appear to have gone further by parceling out a specific function to a tax-exempt group that is expected to flank his eventual campaign.

Steel has served as Boehner’s press secretary since 2008, chiefly responsible for handling daily interactions with the congressional press corps and implementing a broader communications strategy, especially during high-stakes negotiations over formation of the “super committee” in 2011, the 2012 “fiscal cliff” and the 2013 government shutdown.

Boehner has voiced support for Bush generally in the past but is not expected to endorse any candidate before a nominee is chosen. He praised his outgoing spokesman in a statement on Monday, calling him “a pro’s pro.”