(CNN) In one fell swoop Tuesday, President Donald Trump signaled to Republican lawmakers they have a serious problem with Russia -- and they responded.

Trump said he fired former FBI Director James Comey on Tuesday because he was being a "showboat, " but critics quickly alleged the decision was made to curtail the FBI investigation into possible coordination between Trump's campaign and Russian operatives.

However, the high-profile dismissal had the opposite effect in the Capitol, driving Republican lawmakers to take more concrete steps to address the situation.

While GOP members of Congress have a lengthy and ambitious agenda they want to work with the White House to enact, the earth-shattering developments of the week made the issue of investigating the possible ties between Moscow and the President's campaign impossible to ignore.

Senate intelligence Chairman Richard Burr, the leader of the chamber's Russia investigation, immediately said he was "troubled" by Trump's firing of Comey. A few days later, he delivered an update to Senate Republicans on the progress of the Senate investigation.

Burr used the very first question in a Thursday Senate hearing, where Comey was supposed to have addressed lawmakers on global threats, to ask acting FBI Director Andrew McCabe whether Trump was correct when he claimed that Comey told him three times he was not the subject of an investigation.

"Did you ever hear Director Comey tell the President he was not the subject of an investigation?" Burr asked. McCabe responded that he could not answer directly, but, later in the hearing cast doubt on the veracity of Trump's claims that an FBI director would comment to someone connected to an active investigation.

Behind the scenes, Democrats in the Capitol noted the shift in Burr's tone, and took that as a sign that he was getting even more serious about the Senate Russia investigation than he already was.

Senate Majority Leader Mitch McConnell supported Trump's decision to fire Comey -- saying it was within his bounds as chief executive. But the Kentucky Republican also supported Senate Democratic Leader Chuck Schumer's request to have Deputy Attorney General Rod Rosenstein address senators next week on the Comey firing -- a decision that will keep the Russia investigation in the headlines.

And numerous other Senate Republicans expressed deep concerns this week with how Trump's decision to fire the director of the FBI while the bureau was conducting an investigation of Trump's own campaign.

Comey's firing galvanized Democrats this week -- beginning with an almost-universal call to appoint a special prosecutor, and growing into calls from top Democrats like Sen. Dick Durbin and Sen. Dianne Feinstein for Rosenstein to recuse himself.

But the effect of Trump's sporadic decision has been more subtle among Republicans.

Republicans are generally not supportive of either appointing a special prosecutor or a special counsel -- the two are separate independent investigators -- and appear unlikely to come around to the idea being pushed hard by Democrats anytime soon.

"I think Rod Rosenstein, the new deputy attorney general is competent to lead that effort ... The Senate intelligence committee is doing an oversight investigation," said Sen. John Cornyn, the Senate's second-ranking Republican and a member of the Senate Russian investigation. "We have unprecedented access to raw intelligence and just finished intelligence products. And of course most of this investigation is taking place in a classified setting because of its nature. So I have confidence in the leadership of Sen. Burr and (ranking Democrat) Sen. (Mark) Warner to lead this bipartisan investigation."

Burr, meanwhile, has cautioned that investigators are maintaining a steady pace and will not be distracted -- he told reporters that he has no plans to investigate Comey's firing.

The reactions Wednesday, as senators returned to the Capitol a little more than 12 hours after the firing, were also indicative of the ambivalence -- more reminiscent of how lawmakers responded to Trump's erratic tweets during the 2016 campaign.

Sen. Todd Young of Indiana was spotted urging a reporter to get in touch with his office as he tried to hop on the Senate subway. Sen. Joni Ernst told reporters that she needed more time to review what happened.

In an interesting twist, Sen. Lindsey Graham, who is leading his own inquiry into Russia's interference and has been a routine critic of Trump's from within the Republican Party, quickly and fully supported Trump's firing of Comey

One of the most telling comments in the aftermath was actually 24 hours of silence from House Speaker Paul Ryan before saying he supported Trump's decision.

The delay from Ryan harkened back to his own tepid relationship to Trump through parts of the campaign. A little more than a year ago, after Trump was the last Republican standing in the race, Ryan said he still was not certain he would back Trump.

"I'm not there right now," Ryan told CNN's Jake Tapper at the time.

On Friday, Ryan more forcefully distanced himself from Trump, while not commenting on Comey or Russia specifically.

"I'm going leave it to the President to talk about and defend his tweets," Ryan told local station WITI in his home district in Wisconsin. "You know what I'm focusing on, Ken? I'm focusing on what's in my control, and that is what is Congress doing to solve people's problems."

Largely spared from the intraparty soul-searching spurred by the Comey firing this week were other House Republicans, who were on recess outside Washington. But they return to Washington next week, and Comey and the Russia investigations are still front and center.