Sen. Marco Rubio (R-Fla.) at the Conservative Political Action Conference. (EPA/PETE MAROVICH)

Sen. Marco Rubio has recruited Rich Beeson, a veteran political operative and senior official on Mitt Romney's 2012 campaign, to join his likely presidential campaign, according to two Republicans with knowledge of the move.

Beeson is on tap to have a portfolio that includes political and field operations, and may serve as Rubio's deputy campaign manager should the Florida senator move forward officially with his widely expected bid for the 2016 Republican presidential nomination, said the sources, who requested anonymity because they were not authorized to discuss the matter.

Beeson did not respond to a request for comment, and a Rubio spokesman declined to comment.

As Romney's national political director in 2012, Beeson was credited with the campaign's primary state field efforts that helped Romney secure the nomination as well as the general election get-out-the-vote operations. He drew criticism for ORCA, the Romney campaign's voter data system that had serious technical problems on Election Day.

Prior to the Romney campaign, Beeson -- who has deep roots in the presidential swing state of Colorado -- served as the Republican National Committee's political director, and was a founder of FLS Connect, a voter contact firm.

Beeson is joining an-already formidable Rubio political team that includes Terry Sullivan, who now runs the senator's Reclaim America PAC and is seen as a likely campaign manager.

Beeson joins a string of former Romney officials who have already signed on with Rubio. In February, Jim Merrill, a top New Hampshire operative who ran Romney's 2008 and 2012 campaigns in the first-in-the-nation primary state, came on board to oversee Rubio's PAC's efforts in the Northeast and is slated to lead his likely campaign in New Hampshire.

Rubio and his associates have spent months nurturing their relationships with Romney’s former advisers and donors, making the case for the senator in a series of conversations and meetings, all with the hope of slowly winning over Romney's inner circle. They have also been encouraged by the warm words of Spencer Zwick, a longtime Romney confidant who served as his national finance chairman.

Zwick, in an interview Thursday, said he remains unaffiliated in the 2016 race and has no timeline for making a decision about which candidate to back, but has been in touch with and impressed by Rubio's efforts.

“Senator Rubio is starting to build a campaign team and he has a message that resonates," Zwick said. "I like him a lot and I look forward to getting to know him more in the coming weeks.”

In January, when Romney decided to stay out of the 2016 race, the former Massachusetts governor said, “I believe that one of our next generation of Republican leaders, one who may not be as well known as I am today...may well emerge as being better able to defeat the Democrat nominee."

Several people in Rubio’s orbit interpreted the comment as a subtle nod toward the Florida senator, who -- unlike former Florida governor Jeb Bush -- is a fresher face on the political scene. In talks with Romney donors and former aides, Rubio's friends have brought up Romney's message as part of their pitch.

Seeking out Romney's former policy aides has been another endeavor as Rubio looks to cast himself as a thoughtful and well-versed contender. According to a Rubio ally, who requested anonymity to discuss a private gathering, Rubio met Tuesday in Washington with former Romney policy director Lanhee Chen, who remains unaffiliated. Chen, who is a fellow at the Hoover Institution at Stanford University, declined to comment.

Rubio is widely expected to formally launch his presidential bid in April, but aides stressed on Thursday that no final decision has been made yet on the timing or venue for the announcement.

Although he has been overshadowed at the start of the 2016 cycle by Bush and Wisconsin Gov. Scott Walker (R), Rubio has generated buzz in recent weeks among Republican insiders. His speeches at recent donor conclaves, including at the Club for Growth a couple weeks ago in Palm Beach, Fla., drew rave reviews.

Rubio has said he has calculated that he can raise the funds needed to mount a serious presidential bid. Last week, for instance, The Washington Post reported that Norman Braman, a billionaire South Florida auto dealer, was willing to donate as much as $10 million to Rubio or his expected super PAC to help launch his campaign.

In a Fox News Channel interview on Monday, Rubio said, "I feel confident that we’re going to meet that number and exceed it -- I do, and I wouldn’t run for president if I didn’t think we could. So for me, that decision's been made."

Ed O'Keefe contributed to this report.