Senate Republicans and conservative groups quickly rallied behind President Trump's nomination of Judge Neil Gorsuch to the Supreme Court, as Democrats focused on lingering anger over another jurist, Merrick Garland. Meanwhile, Trump encouraged Senate Majority Leader Mitch McConnell to "go nuclear" should Democrats hold up the nomination with a filibuster.
"I had hoped that President Trump would work in a bipartisan way to pick a mainstream nominee like Merrick Garland and bring the country together," Sen. Patrick Leahy, D-Vt., a top Democrat on the Judiciary Committee, said in a statement in which he pledged a "thorough and unsparing" confirmation process for Gorsuch.
Democrats' lingering anger over McConnell's decision to block any consideration of President Obama's nominee to the Supreme Court almost a year ago is critical to understanding why Gorsuch's nomination is likely to play out as an angry, partisan battle over an otherwise highly regarded jurist.
Democratic Sen. Jeff Merkley of Oregon had already announced he would filibuster Trump's nominee before it was made public.
"There is only one person in America who is a legitimate selection: Judge Merrick Garland," Merkley said in a fundraising appeal Monday.
By late Tuesday, another four Senate Democrats had already announced they would oppose his nomination: Sherrod Brown of Ohio, Ron Wyden of Oregon, and Elizabeth Warren and Ed Markey of Massachusetts.
"Before even joining the bench, he advocated to make it easier for public companies to defraud investors," Warren wrote on Facebook. "As a judge, he has twisted himself into a pretzel to make sure the rules favor giant companies over workers and individual Americans. He has sided with employers who deny wages, improperly fire workers, or retaliate against whistleblowers for misconduct. He has ruled against workers in all manner of discrimination cases. And he has demonstrated hostility toward women's access to basic health care."
Warren's opposition will help galvanize progressive activists and groups against the nomination.
"Rewarding Republicans' unprecedented obstruction of President Obama's nominee would be a total abdication of responsibility by Senate Democrats that would haunt them for the rest of their careers," said Murshed Zaheed, political director for CREDO, a progressive communications company.
Abortion-rights groups, including EMILY's List and NARAL, were also gearing up to oppose Gorsuch's nomination.
Senate Democrats are already battling the Trump administration over his Cabinet picks, a factor that has amplified partisan anger on Capitol Hill less than two weeks into the new administration.
"It is time to get over the fact that they lost the election," McConnell said Tuesday of Democrats' delay tactics.
While Democrats can't filibuster Trump's Cabinet nominees, they can still force a 60-vote hurdle on Supreme Court nominees, and they intend to do so. Gorsuch's nomination is likely to reignite debate over the "nuclear option" in the Senate and whether the majority should force a rules change in the Senate to lower that threshold to 51 votes, as Democrats did in 2013 for all non-Supreme Court executive branch nominees.
McConnell generally opposes invoking the nuclear option, but an unpredictable political climate awaits.
On Wednesday, Trump told reporters at the start of a White House meeting with conservative activists who support the nomination that he would urge McConnell to take that step if necessary.
"If we end up with that gridlock" in the Senate, Trump said, he would tell McConnell, "If you can, Mitch, go nuclear."
For their part, Republicans are lining up behind Gorsuch, who is cast as an intellectual heir to the late conservative Justice Antonin Scalia.
"By all accounts, he has the right temperament and experience for the job," said Sen. Marco Rubio, R-Fla., who argued Republicans just won the White House and maintained control of Congress in an election in which Trump campaigned specifically on nominating a conservative to the court.
"On the issue of this Supreme Court nomination specifically, the American people gave the president and the Republican-controlled Senate a mandate to choose a successor to Antonin Scalia," Rubio said.
McConnell noted that Gorsuch's 2006 nomination to the appellate court was approved by voice vote in the Senate, and he called on senators to "respect the result of the recent election" and ultimately allow a vote on the nomination. Republicans have 52 votes in the Senate, and barring something unforeseen in the confirmation process, the party is likely to be unified behind Gorsuch.
Senate Republicans say Gorsuch's nomination could be ready for a Senate vote by early April, citing past confirmation timelines. Democrats have already indicated they're in no rush.
"Judge Gorsuch has a long record, and it will take time to conduct a thorough review," said Judiciary Committee Ranking Member Dianne Feinstein of California. "At a time when public trust in our institutions is at an all-time low and our country is bitterly divided, a thorough and fair review is vitally important."
This story was updated with President Trump's remarks.