Republicans are withholding their judgment on whether President Trump sought to obstruct justice by firing FBI Director James Comey until they hear directly from Comey, and are most ignoring efforts by Democrats to label Trump "guilty" until then.

Democrats have pushed hard to turn Trump's actions into a constitutional crisis, one born out of what they say is Trump's effort to hinder the FBI's investigation into Russia's election meddling and alleged collusion with Trump.

But on Wednesday, some of that pressure eased when the Justice Department announced that Robert Mueller will be a special prosecutor to investigate Trump's links to Russia. Just before that announcement, Democrats said they had momentum on their side.

"The political dynamic is shifting seismically," Sen. Richard Blumenthal, D-Conn., told the Washington Examiner. "Just coming from the floor now, talking to five of my Republican colleagues, they are moving in the direction of, we need to do something."

With Mueller's appointment, Republicans will likely be able to maintain their position that they need to hear from Comey directly before they judge Trump's actions. Most GOP lawmakers resisted the idea of an outside investigation before the Justice Department announcement, and said they wanted the investigations in the House and Senate to proceed.

"You've got a House process going on, a Senate process going on, let it work," said House Natural Resources Committee Chairman Rob Bishop, R-Utah.

House Oversight and Government Reform Committee Chairman Jason Chaffetz, R-Utah, has scheduled a hearing Wednesday featuring Comey, but Comey has not yet confirmed he will testify.

Comey has also been invited to testify both publicly and privately at a Senate Intelligence Hearing, Sen. Mark Warner, D-Va., said Wednesday.

"There are already investigations that are ongoing," said Rep. Dave Reichert, R-Wash. "It's important for us to see them come forward with some information."

"If the facts show there is something real, then this will go in one direction," said Rep. Mario Diaz-Balart, R-Fla. "If it is all hearsay, then it will die down. There are stories of what [Comey] was told and what he wasn't told. Right now, it's just stories."

Even those who quickly endorsed an independent probe say Comey's testimony will be critical.

"I think if Comey makes this public by testifying, it could change the dynamics," said Rep. Walter Jones, R-N.C. "It does depend on what he says, but obviously if he is going to go public, then I think he's got a lot to say."

Jones is one of only two Republican lawmakers to sign onto Democratic legislation to set up an independent commission to investigate Trump.

In between now and Comey's testimony, Republicans are by and large still backing Trump. When asked whether he backs the president, Speaker Paul Ryan, R-Wis., told reporters, "I do," as he exited a press conference.

Ryan also endorsed a threat by the House Oversight and Government Reform Committee to subpoena the FBI for the Comey memo, but made it clear that for now, the GOP is on a fact-finding mission.

"There are a lot of unanswered questions," Ryan said. "What I told our members is now is the time to gather all the pertinent information. Our job is to be responsible, sober, and focus only on gathering the facts. That is what Congress does in conducting oversight of the Executive Branch."

Rep. Mike Simpson, R-Idaho, said most lawmakers are choosing to "keep their powder dry" on Trump for now, perhaps because many can recall the downfall of President Richard Nixon.

"I can remember the start of it," Simpson said. "It was a lot similar to what is going on right now. Fake news, bad reports. Then, the next day something else happens and you've got an avalanche of stuff. People have a memory of that."