WASHINGTON — The news photographers rushed to the front of the room, jutting their lenses at Sen. Marco Rubio of Florida. Colleagues on the Senate Foreign Relations Committee chuckled at the spectacle, which Rubio built up over weeks, ensuring a return to the national spotlight.

On President Donald Trump's first full weekday in office, Rubio faced a consequential decision: maintain an election promise to stand up to Trump or set aside objections to Rex Tillerson, the nominee for secretary of state, and spare Trump a measure of dissent from fellow Republicans.

"It was a close call," Rubio said after the vote Monday, engulfed by reporters. A woman in a Greenpeace shirt joined the herd, mockingly holding up a model of a human spine.

Rubio's vote in favor of Tillerson, despite concern about the former ExxonMobil CEO's coziness with Russia, illustrates a reality and a calculation. This is Trump's Washington, and Rubio, who as a presidential candidate accused Trump of being a con man, is choosing a safer route.

The 45-year-old starts his second term with an opportunity to address longtime criticism that he is more flash than substance, a charismatic speaker who spent a great deal of his first six-year term angling for the presidency, as he likely would have done had Hillary Clinton prevailed.

"He won a very convincing re-election and now he needs to get down on the grindstone," said Al Cardenas, the former Florida GOP chairman who two decades ago cultivated Rubio's entry into politics. "He was MIA for a while. He's got a chance to really shine; he just has to take leadership on a couple of big ideas and move them forward."

Republicans now have the White House to complement control of the House and Senate and can move on promises to get rid of the Affordable Care Act, strip away business regulation and install a conservative on the Supreme Court. It puts the 2020 angling to rest, for now.

"Because we have a Republican president, it precludes all these guys from having to gear up to run," said U.S. Rep. Tom Rooney, R-Okeechobee, who thought it was a mistake for Rubio to rule out a second Senate term as he sought the White House — a promise Rubio broke.

"I think Marco could be an amazing senator. It's great that we get to hear his voice as a legislator, especially on matters of national security and foreign affairs."

Trump's America First outlook complicates Rubio's vision of more active engagement abroad, diplomatically and militarily. Rubio made headlines with aggressive questioning of Tillerson over Russia and its president, Vladimir Putin. Tillerson did not alleviate all the concerns, but Rubio still voted to advance his nomination.

"If he had stood up and voted no based on every criteria he laid out, it would have been Marco Rubio media hero, 'Little Marco' no more," said Eric Jotkoff, a Democratic strategist from Florida, using the nickname Trump gave Rubio during the nasty GOP primary. "But he chose the more politically expedient route or, as he even put it, he chose not to create a political problem for the president. That doesn't sound like someone putting a check on him. That's literally the definition of a rubber stamp."

The alternate view, expressed by some Republicans, is that Rubio did his job in vetting Tillerson when other lawmakers were eager to wave him through, despite sharing concerns about Russia. Rubio insists he won't hesitate to speak up again.

"If he takes policy measures that I disagree with, I'll do what I can as a senator to either stop them or condemn, and when he does things that are good, I'll be there to support him," Rubio said. "I think he deserves a chance to be successful."

This straddling reflects the same line Rubio walked with Trump during the general election. Now he must find a new way forward. Rubio declined to be interviewed and his staff would not outline his priorities, but some signs have emerged.

Burned by a role in the 2013 immigration overhaul, Rubio appears ready to take a back seat as other lawmakers tackle the issue. Rubio kept a low profile as Trump made numerous controversial statements in his first week and said he wanted to begin construction of a border wall that would cost tens of billions of dollars, a move that led to the cancellation of a visit by Mexican President Enrique Peña Nieto.

Rubio already has offered a raft of bills, from antiabortion measures to addressing problems with the Department of Veterans Affairs. He joined a push for tougher sanctions against Russia that may get a cold reception from Trump. And he partnered with Sen. Tim Kaine of Virginia, Clinton's running mate, on a bill that would push the State Department to more closely track growing anti-Semitism in Europe.

"We disagree on a number of things, but if he agrees with you, you can make something happen," Kaine, a member of the Foreign Relations Committee, said in an interview. "I look forward to working with him. He has a carefully thought-out view of a global philosophy for America's role."

This term, Rubio has joined the Appropriations Committee, which affords him a key role in writing legislation allocating federal funds to government agencies. He retains seats on the Intelligence Committee, the Special Committee on Aging and the Committee on Small Business and Entrepreneurship, in addition to Foreign Relations.

"He can actually try to make a difference in the Senate and not at least overtly worry so much about that next office," said Aubrey Jewett, a political science professor at the University of Central Florida. "Of course, if he can do that, he will enhance his future political chances. The main thing he needs to combat is the impression that perhaps he's a bit of a lightweight. This is an opportunity to start changing that image."

The former Florida House speaker was elected to the Senate in 2010 during the rise of the tea party. Almost immediately, Rubio prepared a run for president and assembled a team of consultants. He entered the race with a call for a new generation of leaders — a salvo directed not just at Clinton but Republican rivals such as Jeb Bush.

"He gives a good speech and sounded much more reasonable, populist and accessible than much of the rest of the GOP field," a Clinton ally reported in a private message that surfaced in the hack of Democratic emails that has been tied to Russia. "Felt more like an inspiring Democratic speech than a GOP candidate."

After he dropped out, Rubio declared support for Trump but did not campaign with him and refused to commit to serving the full six-year Senate term, the apparent underlying calculation being that Clinton would win.

Now Rubio faces the new order and is proceeding cautiously.

"I don't think I'm breaking news here to say that President Trump is an unorthodox political figure. I saw it firsthand in the campaign," he told reporters Monday. "But that's who the American people chose. … I want him to succeed because it's good for our country if he succeeds."

Rubio and other Republicans could be watching for stumbles. "If he's not successful, in four years from now voters will have a chance to pronounce themselves," he said.

Trump is already talking about the next election. Meantime, Rubio maintains a national fan base. He has retained his crew of political advisers, paying them through his Reclaim America political action committee. On Oct. 31, the PAC sent $35,000 to the Republican Party of Iowa, funds that went toward helping legislative candidates.

"It helps Iowans to continue to have this positive feeling toward him and a belief that he's a player on the national stage," said Iowa GOP chairman Jeff Kaufmann. He doubts Rubio would mount a primary challenge to Trump, who enjoys deep support in the state that holds the first nominating contest.

"It would have to be an almost Nixonian kind of mistake from Trump," Kaufmann said. "But it's hard for me to visualize a 2024 presidential season without Marco Rubio playing a significant role."

Rubio will be 53.

Contact Alex Leary at aleary@tampabay.com. Follow @learyreports.