Congressional Republicans and Democrats praised the Justice Department's decision to appoint Robert Mueller III as special counsel to investigate possible coordination between Trump associates and Russia in the 2016 campaign - sparking a rare moment of bipartisanship on Capitol Hill over a politically charged issue.
Nevertheless, the Senate and House committees conducting their own inquiries pledged to move forward, setting up a complex landscape of potentially conflicting investigations - and competing goals. Democrats have accused Republicans of making a show of investigating the Trump campaign's ties to Russia. Several of them, along with some Republicans, said Wednesday that the news of a special counsel investigation should not slow down Congress's work - and Republican leaders pledged that it wouldn't.
Senate Intelligence Committee Chairman Richard Burr, R-N.C., whose panel is conducting one of five congressional probes that are directly or indirectly looking into Russian activity, was among those who hailed the news while also declaring that "our task hasn't changed."
"By having someone like Bob Mueller head the investigation assures the American people that there's no undue influence, be it here or be it at the other end of Pennsylvania Avenue, or within the Justice Department or FBI," Burr said.
Rep. Adam Schiff (Calif.), the ranking Democrat on the House Intelligence Committee, was more forceful. "The appointment of a special counsel is not a substitute for a vigorous investigation in Congress and the House Intelligence Committee will take steps to make sure our investigations do not conflict and ensure the success of both efforts," he said. "We will also want to make certain that the special counsel has all the resources it needs to undertake this important task."
The announcement came toward the end of a day in which a growing number of congressional Republicans expressed fresh concerns about the news that President Trump had leaked highly classified information to Russian officials - and the report that he had urged former FBI director James Comey to drop his investigation into former Trump national security adviser Michael Flynn's ties to Russia.
Throughout the day, lawmakers sounded some of their most aggressive notes toward Trump since he took office. Some GOP lawmakers drew parallels to Richard M. Nixon and the Watergate scandal that sunk his presidency, while others raised the possibility of impeachment if Trump's conversation with Comey is determined to have been an obstruction of justice.
Rep. Justin Amash, R-Mich., who has often clashed with Trump and other GOP leaders, replied "yes" when a reporter asked whether there could be grounds for impeaching Trump, if Trump's request of Comey was confirmed.
Meanwhile, the Senate Intelligence and Judiciary committees asked the FBI for documents related to Comey, who was leading an investigation into Russian interference in the election before Trump fired him last week.
The widespread approval of Mueller's appointment followed several weeks during which many congressional Republicans, including House Speaker Paul Ryan (Wis.) and Senate Majority Leader Mitch McConnell (Ky.), declined to call for one. Before Wednesday, many of them touted the congressional investigations as sufficiently independent entities.
But in the hours after Deputy Attorney General Rod Rosenstein announced the move, Republicans spoke mostly about it in positive tones.
"My priority has been to ensure thorough and independent investigations are allowed to follow the facts wherever they may lead," Ryan said in a statement. "That is what we've been doing here in the House. The addition of Robert Mueller as special counsel is consistent with this goal, and I welcome his role at the Department of Justice."
By Wednesday evening, McConnell had not commented on Mueller's appointment.
Rep. K. Michael Conaway, R-Texas, who is leading the House Intelligence Committee's investigation into Russian meddling, said his panel's investigation will continue. "If we find criminal things . . . we'll definitely refer those to Justice," he said. "But the importance of our investigation I don't think is diminished in the least."
That sentiment was echoed by many lawmakers already participating in ongoing investigations.
"This effort should in no way be allowed to impede the ability of the Senate Intelligence Committee to conduct and conclude its investigation into the same subject," said Sen. Marco Rubio, R-Fla. "It is my hope that these investigations will now move expeditiously."
Lawmakers also heaped praise on Mueller's credentials.
"Mueller is a great selection. Impeccable credentials. Should be widely accepted," tweeted House Oversight and Government Reform Committee Chairman Jason Chaffetz, R-Utah.
Rep. Mike Coffman, R-Colo., one of his party's most imperiled lawmakers in next year's elections, said Mueller "has got a good background in terms of not being partisan and I hope he gets down to the bottom of what really is a growing list of allegations." Rep. Barbara Comstock, R-Va., another embattled incumbent, tweeted that appointing Mueller was the "Right thing to do and the right choice."
But senior Democrats cautioned that Mueller should be permitted a wide berth as his investigation commences.
"A special prosecutor is the first step, but it cannot be the last," House Minority Leader Nancy Pelosi, D-Calif., said in a statement. She reiterated her caucus's support for an independent commission to also probe the matter, saying that Mueller "does not negate the need for vigorous congressional investigations."
Pelosi called on the Justice Department to allow Mueller to review "Trump's attempt to intervene" on behalf of Flynn. Similarly, Sen. Patrick Leahy, D-Vt., a senior member of the Judiciary Committee, said Mueller's probe "should extend to the circumstances that led to the president's abrupt dismissal of James B. Comey, and to other critical matters that arise."
Rep. Mark Meadows, R-N.C., chairman of the generally pro-Trump House Freedom Caucus, was one of the few lawmakers to offer some caution about Mueller's appointment. Although Meadows called the appointment "a prudent move," he also suggested that Mueller "comes with more credibility on the Democrat side than on the Republican side," a remark he said was based on "sworn testimony that he's given here on Capitol Hill since I've been here."
Earlier in the day, Republicans were leveling serious criticism against Trump over his controversies and edging closer to acquiescing to long-standing Democratic demands for an independent investigator.
Still, many rank-and-file GOP members said Wednesday that they were not alarmed by the explosive reports about the president's conversations with Comey and Russian officials. Ryan and McConnell spent much of the day trying to direct public attention beyond the firestorm.
Rep. Robert Aderholt, R-Ala., was among the lawmakers who claimed to be untroubled by the developments. "It's very clear there are a lot of people who want to see the president distracted," said Aderholt, adding that back in Alabama, there is "a lot of frustration that they're not allowing him to do his job."
The uneven response has fueled widespread anxiety on Capitol Hill about the future of the ambitious agenda Republicans embarked on after assuming control of Congress and the White House in January. Republicans recognize that if they turn fully against Trump, they will lose their most critical legislative partner. But they are also showing increasing worry that sidestepping a president blanketed in controversy is no longer tenable.
"It is a serious issue the way other scandals have been serious issues," said Sen. John McCain, R-Ariz., who the previous evening had compared the current imbroglio to the Watergate saga.
"What I was saying was that these scandals need to be completely - all the information needs to get out as quickly as possible so we can resolve the issue and move forward," said McCain.
The revelation that Comey had written in a memo that Trump pressured him to drop an investigation into Flynn compounded earlier worries about Trump's decisions to share highly classified material with Russia and abruptly oust his FBI chief.
Asked if the allegations facing Trump concern potentially impeachable offenses, Rep. Mike Simpson, R-Idaho, said, "I don't want to go there. I don't know yet."
But the beginnings of the scandal that ultimately prompted Nixon's resignation, Simpson said, "was a lot similar to what was going on now: Ah, 'fake news,' 'bad reports,' 'that didn't happen,' etc., etc., etc. Well, yeah, this did happen, and then the next day something else happens, and pretty soon you've got an avalanche of stuff."
Asked about GOP lawmakers making comparisons to the Watergate scandal, White House press secretary Sean Spicer said Trump was focused on his visit Thursday with the Colombian president and preparing for his trip to the Middle East and Europe that begins on Friday.
The Washington Post's Paul Kane, David Weigel, Karoun Demirjian, Kelsey Snell and Amber Phillips contributed to this report.