Nicole Gaudiano

USA TODAY

WASHINGTON — Democrats are ramping up pressure on Republicans to join them in calling for an independent investigator to take over the FBI’s probe of possible collusion between President Trump’s campaign and the Russian government.

Senate Democratic Leader Charles Schumer of New York and other Democratic senators say they will wait for a special prosecutor to be appointed before they will vote on a nominee to replace former FBI Director James Comey, who many believe President Trump fired last week because of the bureau’s Russia investigation.

Democrats believe a closed, all-senators meeting on Thursday with Deputy Attorney General Rod Rosenstein — who along with Attorney General Jeff Sessions recommended Comey’s firing — will provide information to bolster their case for a special prosecutor.

“A special counsel must be appointed before we consider a new nominee for FBI director, and that nominee needs to be closely scrutinized by the Senate,” Sen. Tom Udall, D-N.M., said in a Senate floor speech. “This person will be responsible for restoring Americans’ confidence in the FBI and ensuring that he or she does not pledge loyalty to the president, but pledges loyalty to the Constitution.”

In the House, Democrats will start Wednesday to try to force a vote on legislation to create an independent commission to take over the FBI’s ongoing probe.

“The question remains: What do the Russians have on President Trump financially, politically and personally that he and Republicans in Congress want to hide?” House Democratic Leader Nancy Pelosi wrote in a letter Monday to colleagues.

As the minority party in both chambers, Democrats likely don’t have the votes to push legislation for an independent commission. But Senate Democrats can use procedural delay tactics that would slow Senate business or effectively shut it down, as they did one day last week.

“Their ability to apply the brakes to the president’s legislative program is a power that they still possess,” said Ross Baker, a political science professor at Rutgers University. “It doesn’t mean they can defeat anything but they can make the process much slower and more agonizing. And that’s the type of thing that can get under President Trump’s skin.”

Sen. Dick Durbin, the Senate’s No. 2 Democrat, said in an interview that Democrats would rather not resort to such delay tactics.

“It seems to me that, at some point, the Republicans have got to conclude that a special prosecutor is their best answer to the many criticisms ... that they have not been as vocal or negative to Trump,” he said.

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A handful of House Republicans said the latest controversy about Trump and Russia underscores the need for a special prosecutor to investigate Russia's interference in last year's U.S. presidential election and possible collusion between the Trump campaign and Russian officials.

"I continue to support any efforts done by the House Intelligence Committee and join many of my colleagues in supporting the assignment of a special prosecutor to take over the ongoing FBI investigation," said Rep. Steve Knight, R-Calif., who represents a swing district.

Democrats are focused on laying out their case for Republicans and the public. Members of the Senate Judiciary Committee have asked the Department of Justice Inspector General to investigate Trump’s sudden firing of Comey. They also believe Senate briefings from Rosenstein – along with Sessions and Comey, if they will appear before Congress – will further demonstrate the need for a special prosecutor.

In recommending Comey’s firing, Rosenstein cited Comey’s controversial handling of the investigation into former secretary of State Hillary Clinton’s use of a private email server. But Trump told NBC last week that he was thinking of “this Russia thing” when he made the decision, calling it a “made-up story.”

The decision to appoint a special counsel falls to Rosenstein because Sessions recused himself from the investigation, but Rosenstein has indicated he’s not willing to do that. Senate Majority Leader Mitch McConnell, of Kentucky, has said opening a new probe would “only serve to impede the current work being done” by the Senate Intelligence Committee.

But Sen. Richard Blumenthal, D-Conn., said he will move forward with legislation to give a three-judge panel the power to appoint a special prosecutor if Rosenstein on Thursday says he won’t do it.

Schumer has said Senate Democrats agree that the Justice Department's highest-ranking career civil servant — not Rosenstein — should be responsible for appointing a special prosecutor because "serious doubt has been cast on Mr. Rosenstein's impartiality."

Matt Miller, a Justice Department spokesman under former President Obama, said Rosenstein’s briefing will help Democrats build a factual case for a special prosecutor, particularly if he will discuss his conversations with Trump about Comey’s firing.

“It’s going to be clear after that meeting that it’s very difficult for him to both oversee the Russia investigation and have helped the president fire the FBI director who was conducting it,” Miller said. “It’s impossible for him to have good answers in this meeting.”

An NBC-Wall Street Journal poll released Sunday found 78% of those surveyed said they would prefer seeing a special prosecutor investigate Russia’s involvement in the 2016 presidential election.

Republicans may not be swayed by the substance of what Rosenstein says, but the meeting will continue to put public pressure on them, Miller said. If Democrats don’t get the answers they need from Rosenstein, Miller said, “everything else has to be on the table, including a full shut down of the Senate until they get some answers.”

Contributing: Heidi Przybyla, Kevin Johnson and Erin Kelly.