The Trump administration has begun its search for a replacement for ousted FBI Director James Comey, with the Justice Department holding interviews for an interim successor as Washington absorbed the shock of the president’s decision to fire the nation’s top law enforcement officer.

The quest for a temporary director may pass over Comey’s deputy, Andrew McCabe, who ascended to the post Tuesday but has faced past criticism from President Donald Trump. Attorney General Jeff Sessions and Deputy Attorney General Rod Rosenstein will spend most of Wednesday interviewing candidates, according to a department official who briefed reporters on condition of anonymity.

An acting director could be named as soon as Wednesday, according to a second Justice Department official. Candidates being interviewed include Adam Lee, special agent in charge of the FBI’s Richmond office; Michael Anderson, special agent in charge of the Chicago office; Paul Abbate, the FBI’s executive assistant director in charge of the bureau’s criminal and cyber division; and William Evanina, the national counterintelligence executive at the Office of the Director of National Intelligence.

Finding a permanent replacement who can win Senate confirmation and earn the trust of rank-and-file FBI agents will be a tall order for the White House after Trump’s move seemed to cross a long-standing tradition against political interference with the bureau. Several FBI agents replaced their photos on Facebook with Comey’s and have written that they were outraged by his removal.

Trump isn’t expected to see any candidates for a permanent replacement on Wednesday, according to a White House official. The president will get a list of possible contenders in coming days, the official said, but it’s unclear whether he’ll meet with any of them before leaving on a foreign trip at the end of next week.

Republican Sen. Bob Corker, chairman of the Senate Foreign Relations Committee, said he called Trump Tuesday night and urged him to nominate “someone who is absolutely beyond reproach and that both sides of the aisle can have complete faith in and the American people will.”

Trump now gets to nominate Comey’s successor while the agency is deep into an investigation of Russian meddling in last year’s presidential campaign, which includes whether anyone close to Trump colluded with the Russians. Democrats condemned Comey’s dismissal, calling it an effort to cut short the probe and demanding the appointment of a special prosecutor to carry it forward.

According to the White House, though, it wasn’t the Russia investigation that led to Comey’s dismissal. Rosenstein said in a memo that Comey was fired because of his handling of the probe into Democratic presidential nominee Hillary Clinton’s private email server – even though the facts of that inquiry were well-known at the time Trump took office and asked Comey to stay on the job.

Comey’s testimony before a Senate panel last week – with its implication that he might again disregard the Justice Department’s chain of command as he did in announcing in July that he was closing the Clinton investigation – was the turning point that sealed his removal, according to the first Justice Department official. His testimony took Sessions and Rosenstein by surprise, according to the official, who declined to comment on whether an effort to remove Comey was under way before his testimony.

The temporary FBI director would lead the bureau until a new director is nominated by Trump and confirmed by the Senate. While McCabe, a career FBI official, already was interviewed for the interim job, according to one of the officials, the possibility that he’ll be passed over could intensify the uproar over Trump’s dismissal of Comey.

McCabe came under scrutiny last year for helping to oversee the investigation of Clinton’s email practices because McCabe’s wife had accepted donations from Democratic political organizations for a failed 2015 election bid to the Virginia state senate. The FBI said in a statement at the time that McCabe “played no role” in his wife’s campaign “and did not participate in fundraising or support of any kind.”

At a rally in Florida in October, Trump told a booing crowd, “So the man that was investigating her from the FBI, his wife runs for office and they give her more than $675,000 to run. And it just came out.”

Now, Trump must recruit a new FBI director who can win Senate confirmation after some Republicans joined Democrats in criticizing the president’s firing of Comey. It’s also unclear whether Trump can convince Comey’s potential successors that they wouldn’t also be fired if they crossed the president.

Republican Sen. Lindsey Graham, who heads a Judiciary subcommittee investigating Russian meddling in last year’s presidential campaign, said he would “prefer that we pick somebody that can get some Democratic support if there’s any reasonable views left on the Democratic side about Trump.” He said the president should pick a professional who “would be seen by most Americans as a good leader for the FBI .”

Senate Democratic Leader Chuck Schumer said that “given the way the president has fired Director Comey, any person who he appoints to lead the Russia investigation will be concerned that he or she will meet the same fate as Director Comey if they run afoul of the administration.”

“We need to hear from this administration about what happened and why, and what is going to happen next,” Schumer said on the Senate floor. He also reiterated his call for a special prosecutor to “get this investigation out of the hands of the FBI and far away from the heavy hand of this administration.”

Speaking before Schumer, Senate Majority Leader Mitch McConnell said a new investigation by a special prosecutor would “impede the current work being done” by the FBI and the Senate Intelligence Committee. He accused Democrats of complaining “about the removal of an FBI director whom they themselves repeatedly and sharply criticized.”

In his memo, Rosenstein faulted Comey for publicly announcing his decision to close the investigation into Clinton’s use of a private email server when she was secretary of state. The director “was wrong to usurp the Attorney General’s authority on July 5, 2016, and announce his conclusion that the case should be closed without prosecution,” Rosenstein said. He added that “it is not the function of the Director to make such an announcement.”

Comey, 56, was appointed by President Barack Obama in 2013 for what would normally be a 10-year term. His handling of the Clinton investigation and the roiling debate over Russian interference in the presidential campaign left him with few political allies in Washington.

He was vilified by Republicans last summer when he initially closed the investigation into Clinton, saying that she and her aides were “extremely careless” in their handling of classified information but that no prosecutor would be able to bring charges.

Democrats faulted Comey for reopening the Clinton email probe just before Election Day while failing to state in public that the agency was investigating possible Trump campaign links to Russian officials. Trump has said there were no such connections.

Comey confirmed in March that the FBI is investigating whether any of Trump’s associates colluded with the Russian government to influence the 2016 campaign for president. He also publicly contradicted Trump’s assertion that the Obama administration “wiretapped” Trump Tower last year.

Comey is only the second FBI chief to have been fired. William Sessions was dismissed by President Bill Clinton and Attorney General Janet Reno in 1993 over financial abuses.

Bloomberg’s Arit John and Laura Litvan contributed.