Senate Democrats have the 41 votes they need to filibuster Donald Trump’s Supreme Court nominee, Neil Gorsuch.

On Monday afternoon, Sen. Chris Coons (D-DE) told reporters that he would be joining the Democratic filibuster against Gorsuch’s nomination.

Senate Majority Leader Mitch McConnell (R-KY) has said he would respond to a filibuster by rewriting the Senate’s rules so that Supreme Court justices need 51 rather than 60 votes to be confirmed. That rule change — called the “nuclear option” on Capitol Hill — would allow Gorsuch to be confirmed without Democratic votes.

Still, Senate Democrats and left-wing activists have sought to force McConnell to use the nuclear option rather than lay down their arms prematurely. Like other Democrats, Coons stressed that he would filibuster Gorsuch in large part because of McConnell’s refusal to give President Barack Obama’s Supreme Court nominee, Merrick Garland, a Senate hearing after Justice Antonin Scalia died in February of last year.

“If seven months of preventing Judge Merrick Garland from getting a hearing and a vote is anything, it’s the most successful partisan filibuster in Senate history,” Coons said. “This is a very close call, and it’s important to not miss that virtually every member of my Congress views this as a stolen seat.”

Republicans were quick to criticize Senate Democrats for their obstructionism, with Sen. Bill Cassidy (R-LA) telling CNN that Gorsuch shouldn’t be rejected simply “because Chuck Schumer fears his left-wing base.”

But for left-wing activists, the willingness of Democrats to stand up to Trump’s nominee is a victory nonetheless.

“We want to see our leaders in Congress standing up as strongly to the Trump administration as we are in the streets and in airports across the country,” Charles Chamberlain, executive director of the advocacy group Democracy for America, told me when Gorsuch’s nomination was announced. “Anything less than a complete and utter rejection of Trump’s Cabinet appointees and of their Supreme Court appointees is absolutely unacceptable.”