NEW CASTLE, N.H. — U.S. Sen. Marco Rubio tore into a dinner roll, clapping politely between determined bites as a man at the podium introduced political candidates in the room. He was hungry after a day of fundraising and interviews with local reporters.

But when the chicken and mashed potatoes arrived, the meal sat untouched, growing cold in the dimly lit ballroom of the Wentworth by the Sea hotel.

Rubio was doing the New Hampshire thing, working the room in a blur of handshakes, hellos and small talk. He posed for cellphone photos and signed autographs. Then he took the stage for a 37-minute speech that ended with a standing ovation from a sold-out crowd of more than 300 Republicans.

Make no mistake, Rubio is testing a run for president.

The Florida Republican's visit Friday to the nation's first primary state underscored eagerness to plant his flag amid an emerging field of possible GOP contenders in 2016. A year ago, he was embroiled in a divisive debate over immigration, imperiled by a conservative base that saw him as an amnesty-backing traitor.

Rubio, who turns 43 later this month, may just talk his way back into contention.

"Every time I speak at events like this and I see bartenders standing behind a rollaway bar, I'm reminded of my father because that's what he did for a living," he said. "He worked all those years at events like this so one day his children could be sitting at one of these tables or even standing at the podium like this."

The audience, some misty-eyed, burst into applause as the immigrant son went on about the American Dream and fears of it slipping away for millions of people. He outlined prescriptions for problems, interrupting at times for jokes like one about a guy who showed up in a Yankees cap — "Don't ever say we're not a big tent but notice he's sitting in the corner" — and jabbing at Democrats and Hillary Clinton.

"Their ideas are stale," said Rubio, wearing a dark suit and bright red tie. "And they are threatening to nominate someone now who wants to take us to the past."

He never mentioned immigration.

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It was Rubio's first visit to the Granite State in nearly two years, part of a calculated effort to tamp down presidential speculation and scrutiny, which conveniently dovetailed with the blowup over immigration. Rubio has turned down about 100 invites in early nominating states, but now sees a need to assert himself. New Hampshire has been paid recent visits by Sens. Rand Paul of Kentucky, Ted Cruz of Texas, and Gov. Bobby Jindal of Louisiana, among others. Former Florida Gov. Jeb Bush hasn't visited, but he has shot to the front of national polls. Rubio's numbers, by contrast, have cooled in the last year.

"This is the most wide-open presidential primary we've ever seen in New Hampshire. There is no heir apparent, no front-runner," said Jim Merrill, a GOP operative who helped Mitt Romney in 2012. "Sen. Rubio is coming up at the right time to make a first impression."

Rubio, who has not said whether he'll seek the presidency or run for another Senate term, may be the best communicator of the lot, with a rhetorical grace and optimism that invokes the current White House occupant, Barack Obama, or the Republican icon who last promised a new morning in America.

"He's a young Ronald Reagan," said Julie Brown, 79, a former state legislator who hosted the former president at her home during the 1980 campaign. Gretchen Jrosky, 43, did not know much about Rubio until seeing him Friday: "To actually hear him speak and tell his story, he's just a real person, a real American. He has young children. If he can get that message across, he's absolutely a viable candidate."

Amid the glowing reception were quieter reservations — about Rubio's experience and his role in crafting the Senate's comprehensive immigration reform bill that would have provided a path to citizenship for up to 11 million illegal immigrants.

"Excellent speech. Excellent," Paula Tarta, 62, told her friends at her table, a flower bouquet in the middle. "Where does he stand on immigration, though? Isn't he for open borders?" Rubio, in fact, helped push for billions of dollars in additional border security funding in the bill, but the inaccurate remark embodies his problem among some conservatives.

Immigration isn't as hot an issue in New Hampshire as other states, including Iowa, whose caucuses are the first presidential nominating contest. Granite State voters tend to focus on economic issues. Independent voters, who make up about 40 percent of the electorate, can vote in partisan primaries.

"I know he took a hit with immigration. But something has to be done and put that whole thing behind us," said Kyle Engle, 51, an airline pilot who lives in nearby Portsmouth. He is an independent but votes Republican. "He's got a good chance of getting a message across that would get him elected. He seems to have a plan."

Rubio spent the past year focused on anything but immigration, wading into policy at an almost frenetic pace, from college affordability to federal wage subsidies for the poor. Tuesday, he'll propose "retirement security" reforms in a speech in Washington.

Tension abroad has provided an opportunity to sharpen his foreign policy credentials, and position himself to the right of fellow Republicans such as Paul, who have called for less military engagement around the world and cuts to the defense budget. Public opinion tilts toward Paul's side but the Republican base aligns with Rubio, which has the added benefit of leveling out his immigration problem.

"The best way to ensure peace is through strength," Rubio said in his speech. Want the military to never go to war? he asked. "Make it a military that can never lose any war."

The applause he drew was matched when he talked about family values and promoting marriage as a way to prevent childhood poverty. He ended on the emotional note he began on, turning back to his Cuban immigrant parents.

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Officially, Rubio was in New Hampshire to help other Republicans, not himself. He began Friday in Boston, headlining a fundraiser for U.S. Sen. Kelly Ayotte. They were elected together in 2010 and have become friends. Last year Rubio used his Reclaim America PAC to fund TV ads defending Ayotte against attacks for a vote against gun control measures. She would be a key ally if he decides to run.

From there, Rubio headed to Bedford, N.H., near Manchester, to raise money for the state GOP. He met with local reporters, including a sit-down for television station WMUR's Sunday show. Rubio also taped an interview for ABC's This Week, which airs this morning.

He arrived at the hotel in New Castle with two strategists, Terry Sullivan and Todd Harris, who work for Rubio's PAC and helped keep him a safe distance from national reporters. Rubio recently shifted Cesar Conda, who has been his Senate chief of staff, to the PAC, a clear sign of a buildup to a campaign. The PAC has spent a lot to build a national donor base, raking in millions.

Democrats did not wait for Rubio to step foot in the state before casting him as too conservative. A news release criticized his opposition to increasing the minimum wage and the Affordable Care Act, and his vote against the Violence Against Women Act.

"With this extreme record, it's no surprise that Marco Rubio has slipped from first to 10th in New Hampshire's Granite State poll of the 2016 Republican primary over the past year," the Democratic National Committee said.

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Rubio's planning for 2016 is complicated by increasing talk about a run by Bush, who has ascended to the top of some polls amid New Jersey Gov. Chris Christie's bridge scandal. Bush has excited top GOP donors across the United States who consider a Washington outsider to be an asset. New Hampshire has a decades-long relationship with the Bush family; George H.W. Bush ran in the 1980 primary.

"The affinity is deep and real," said Tom Rath, a GOP consultant who has advised a string of presidential candidates, including George W. Bush and Romney. "There's a lot of people leaving the light on for Jeb."

Rich Killion, another GOP strategist, said Bush could "pull up a lot of space on the center right, which is the sweet spot of the primary electorate. It would be a big concern for Rubio."

Rubio, who last summer joined the fierce criticism of the Common Core education standards that Bush champions, has indicated he will not take the friendship into account.

"In my mind when people decide to run for an office of that magnitude they do so under their own criteria, not what someone else is going to do," he said on CNN last month. "And I'd imagine Jeb would tell you the same thing."

Alex Leary can be reached at leary@tampabay.com. Follow @LearyReports on Twitter.