Sens. Marco Rubio (R-Fla.) and Susan Collins (R-Maine) arrive for former FBI director James Comey's appearance before the Senate Intelligence Committee on Thursday. (Jim Bourg/Reuters)

In early January, before Donald Trump was sworn in as president, Sen. Marco Rubio took a brief turn as the highest-profile Republican critic of Trump’s emerging foreign policy.

Rubio (R-Fla.) opened his questioning at the Jan. 11 confirmation hearing for Rex Tillerson, Trump’s nominee for secretary of state, with blistering questions about whether the ExxonMobil CEO believed that Russians, at the behest of President Vladi­mir Putin, had interfered with the 2016 presidential election.

Five months later, Trump’s onetime GOP campaign rival displayed a far different demeanor. In Thursday’s Senate Intelligence Committee hearing with James B. Comey, the fired FBI director who testified about his interactions with Trump before his dismissal, Rubio used his seven-minute stint to blunt allegations that the president’s behavior toward Comey constituted an obstruction of the FBI’s counterintelligence investigation of Russia.

Once dismissed by Trump as “Little Marco,” Rubio even homed in on the issue that has most animated the president: leaks of information damaging to him.

“We’ve learned more from the newspapers sometimes than we do from our open hearings, for sure,” Rubio said to Comey. “You ever wonder why of all the things in this investigation, the only thing that’s never been leaked is the fact that the president was not personally under investigation?”

(Sarah Parnass/The Washington Post)

For those wondering whether Republicans are ready to make a sharp break from Trump, think again. Rubio was among a vast majority of the Republicans on the committee who, judging from the questioning of Comey, could well be described as Trump’s political defense team.

Sen. Roy Blunt (R-Mo.), who earlier this year pushed for a more forceful Russia investigation, pressed Comey on his decision to leak a Trump-related memo through a friend to the New York Times. Sen. James Lankford (R-Okla.), who has questioned Trump’s posture toward Russia, dismissed Comey’s claim that Trump was pressuring him to drop the probe as “a pretty light touch.”

And across the Capitol, as Comey was midway through his testimony, House Speaker Paul D. Ryan (R-Wis.) dismissed Trump’s demands of “loyalty” from Comey as the actions of a novice politician who does not understand that the FBI needs to maintain its independence from political influence. “He’s just new to this,” Ryan said of Trump.

Some Democrats were stunned that Republicans did not break away from the president.

“Given the fact pattern, it’s a little surprising,” said Sen. Martin Heinrich (D-N.M.).

Others suggested that the GOP’s reluctance to move against Trump was understandable because the investigation is still in its infancy. “I expected it a bit, to be honest with you,” said Sen. Dianne Feinstein (D-Calif). “I think we’re not at anywhere close to making conclusions.”

Feinstein said it will take many more months before the committee can determine whether the Trump campaign colluded with Russian hackers or Trump committed obstruction of justice. “We’re not there yet,” she said.

Republicans did not succeed in breaking Comey’s stride or expose wrongdoing on his part while running the FBI. Nor did they refute the underlying allegation that Trump fired Comey because he declined to drop portions of the FBI investigation. There are plenty of doubts lurking in Republican minds about what will be unearthed next, sometimes expressed publicly and often expressed privately.

In the early moments Thursday, Comey clearly commanded the hearing room in the Hart Senate Office Building, explaining why he kept highly detailed memos of each of his interactions with Trump from early January until his May 9 firing.

“I was honestly concerned that he might lie about the nature of the meeting,” he said of their first meeting, when he briefed the president-elect about allegations that Russians had obtained compromising information on Trump. “I knew that there might come a day when I’d need a record.”

Many Republicans felt the need to pay homage to Comey’s long career as a federal prosecutor and leader of the FBI. “America needs more like you,” said Sen. James E. Risch (R-Idaho).

But on the political front, Republicans circled back to the idea that this portrait painted by Comey was not good for Trump — yet it was also not a high crime or misdemeanor.

Rubio stood out in part because of his often personal fights with Trump during the 2016 presidential primaries. In January he appeared ready take Tillerson’s nomination down, particularly after Rubio asked whether Putin was a “war criminal.”

“I would not use that term,” the future secretary said.

Later that month, however, Rubio relented, and Tillerson was confirmed on a narrow vote.

Some saw Rubio as a potential maverick in the Intelligence Committee’s investigation, and on Wednesday he was forceful in trying to get Trump’s top intelligence advisers to confirm The Washington Post’s report that the president had asked them to intervene with Comey to get him to drop the Flynn investigation.

On Thursday, however, Rubio kept his questions to Comey in the realm of narrowing the scope of the allegations. He attempted to diminish the impact of the allegation that Trump wanted Comey to “let go” of the Flynn probe. He asked whether Comey responded in any negative fashion: “Did you say anything to the president about — that is not an appropriate request? Or did you tell the White House counsel that is not an appropriate request?”

No, Comey said — and then Rubio asked the questions about leaks. He seemed to be suggesting that Comey or his onetime allies at the FBI were behind the leaks damaging to Trump, asking him to name every member of his senior leadership team with whom he had discussed his interactions with Trump.

Afterward, Rubio told reporters that Trump’s interactions with Comey were probably not appropriate. “Whether it rises to criminality, you know, I think there’s significant doubts about whether it rises to that level,” he said.

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