WASHINGTON — As Democrats geared up for an epic fight they're not likely to win over the next Supreme Court nominee, they spoke with one loud voice: Wait until after the midterm elections.

The news of Justice Anthony Kennedy's retirement dropped like a bomb for Democrats, who have counted on the courts to reign in the Trump administration.

Now, the president will have a chance to appoint another conservative to replace the sometimes swing-voting Kennedy, which Democrats fear will solidify the court's conservative majority and potentially imperil decades of progressive legal precedent on everything from abortion to unions to LGBT rights to Affordable Care Act to the environment.

Democrats cried foul as Senate Majority Leader Mitch McConnell, R-Ky., vowed Wednesday to push ahead with the confirmation of Kennedy's replacement before November's elections — despite refusing to advance President Barack Obama's Supreme Court nominee ahead of the 2016 presidential race.

"This is the most important Supreme Court vacancy for this country in at least a generation," Senate Minority Leader Chuck Schumer, D-N.Y., said on the Senate floor, insisting Americans should have the chance to vote first in the midterms on the senators who will either confirm or deny the nominee.

"Anything but that would be the absolute height of hypocrisy," Schumer said.

McConnell was unmoved by the protestations, saying things are different.

"There's no presidential election this year," McConnell told reporters in explaining why a vote in 2016 would have been wrong but is OK in 2018, before slipping into his office.

Sen. Chris Murphy, D-Conn., said, "It's absolute hypocrisy for the majority leader to move forward on a vote now when he wasn't willing to move forward on a vote ahead of the 2016 election" on Obama nominee Merrick Garland.

The top Democrat on the Senate Judiciary Committee, Dianne Feinstein of California, agreed, saying that the midterms are only four months away and will determine the composition of the Senate.

"There should be no consideration of a Supreme Court nominee until the American people have a chance to weigh in," Feinstein said in a statement. "Leader McConnell set that standard in 2016 when he denied Judge Garland a hearing for nearly a year, and the Senate should follow the McConnell Standard."

Sen. Kamala Harris, D-Calif., who has not ruled out a 2020 White House bid, also said the Senate should wait to consider a high court nominee until after November's elections.

"Given the stakes of this seat which will determine the fate of protected constitutional rights, the American people, who are set to vote in less than four months, deserve to have their voice heard. We should not vote on confirmation until they have voted at the ballot box," she said in a statement.

The President just said the next Supreme Court nominee WILL come from his list of 25 judges that passed his overturning Roe v. Wade litmus test. We need to say NO hearings before the election and work our hearts out and take back the Senate. https://t.co/9HzyIhLQei — Kirsten Gillibrand (@SenGillibrand) June 27, 2018

But other Senate Democrats said they would reserve judgment until Trump nominates Kennedy's successor.

"The president must appoint a fair-minded and open-minded jurist in the mold of Justice Kennedy, a centrist and moderate who will listen to his colleagues because Justice Kennedy was a key vote in some of the critical majorities on issues like reproductive rights, voting rights and other important rights key to the future of America," said Sen. Richard Blumenthal of Connecticut.

"Looking forward to being able to talk and interview all of the candidates (Trump) will be sending forward," Sen. Joe Manchin, D-W.Va., told NBC News.

Asked if Democrats are frustrated that they don't have much power after Senate Republicans changed the rules last year to allow for a simple majority vote to confirm Supreme Court nominees rather than 60 votes, Manchin said, "The system is what it is — it’s broken."

Senate Republicans triggered that "nuclear option" to kill the filibuster in order to clear a path for then-Supreme Court nominee Neil Gorsuch, who is already proving to be a valuable team player for conservatives on the court.

That followed Democrats' move to eliminate the filibuster for lower court nominees in 2013 when they held the majority.

As much incentive as Democrats have to seek a delay in the vote until after Election Day, Nov. 6, Republicans have reason to make sure it takes place before then.

The GOP holds only a narrow 51-49 majority in the Senate, although it will be difficult for Democrats to pick up the two seats they need to flip the chamber given the pro-Republican tilt of this year's Senate map.

So, short of pushing for a delay, Democrats have little real recourse to block the eventual nominee.