Senate Majority Leader Mitch McConnell. Win McNamee/Getty Images Republicans voted on Thursday to change Senate rules to kill the filibuster for Supreme Court nominees, clearing the path for Judge Neil Gorsuch, President Donald Trump's nominee for the high court, to be confirmed.

Senate Majority Leader Mitch McConnell invoked what is known as the "nuclear option" after Republicans initially failed to clear a 60-vote threshold to move forward with Gorsuch's confirmation.

By changing the rules, the Senate can now end debate for Supreme Court nominees with a simple majority instead of 60 votes, effectively killing the filibuster.

The vote to change the rules was 52 to 48, split along party lines. After the rules change, senators voted 55 to 45 to advance Gorsuch's confirmation to a final vote on Friday.

Democrats have employed the tactic before. Harry Reid, the former Senate majority leader, used it in 2013 to assist in the confirmations of President Barack Obama's judicial and executive nominees.

McConnell has said he's not a fan of changing the rules and going "nuclear," but Republicans are steadfast in their desire to get Gorsuch confirmed, and the Kentucky Republican expressed willingness to use the option.

A trio of Democratic senators who represent states Trump won in landslides last fall — Heidi Heitkamp of North Dakota, Joe Donnelly of Indiana, and Joe Manchin of West Virginia — voted with the Republicans to move Gorsuch's nomination along in the initial vote.

But no other Democratic senators broke from the party, including moderates who had been targeted to flip: Jon Tester of Montana, Bill Nelson of Florida, and Claire McCaskill of Missouri, all of whom represented states Trump won.

Democrats view the opposition to Gorsuch, who last month was grilled for more than 20 hours on Capitol Hill by the Senate Judiciary Committee, as an appropriate response to the thwarting of President Barack Obama's choice to fill the vacant seat. Judge Merrick Garland's confirmation was obstructed by Republican senators last year.

Senate Minority Leader Chuck Schumer tried to delay the move to change the Senate rules.

"It doesn't have to be this way," the New York Democrat said. "When a nominee doesn't get enough votes for confirmation, the answer is not to change the rules, it is to change the nominee."

Before entering the Senate chamber, Sen. John McCain of Arizona, who voted to change the rules, called Thursday a "bad day for democracy."

"I think it will clearly lead to more extreme appointments on both sides, and I think it's a terrible mistake that we will regret for many, many years to come," McCain said. "And we're on a slippery slope, no matter what they tell you. We went from the judges to Supreme Court justice. What's next?"

Neil Gorsuch, President Donald Trump's nominee for Supreme Court justice. Chip Somodevilla/Getty Images

Democrats were quick to express their disdain with the decision.

"Republicans stole this seat, and despite Trump's nominee being unable to earn the 60 votes he needed to be confirmed, they're now rigging Senate rules to unilaterally install him on the Supreme Court," Democratic National Committee Chairman Tom Perez said in a statement. "By doing Trump's bidding and turning both the Senate and our highest court into a rubber stamp for the president, Mitch McConnell and Senate Republicans have trampled on the framers' vision of checks and balances."

Sen. Richard Blumenthal of Connecticut called the day "one of my saddest in the Senate" and said the rules change "will have enduring fallout and rippling repercussions."

"Sadder than anything is the damage caused to two pillars of democracy – the Supreme Court and the Senate itself," he said in a statement. "Respect and trust for the court — so essential for the practical force of its rulings – has been gravely undermined by raw political conflict."

Republicans defended the move, praising Gorsuch's credentials and criticizing Democrats for their obstruction.

"Judge Gorsuch is a principled jurist who is steadfast in his commitment to defending the Constitution," Sen. David Perdue of Georgia said in a statement. "Democrats have agreed, and they confirmed Judge Gorsuch without objection in 2006. That's why it is ridiculous Democrats today put self-interest and party interest ahead of the nation's interest. Republicans this year have said all along we'll do what it takes to get Judge Gorsuch the up-or-down vote he deserves, and next week he will be an associate justice on the United States Supreme Court."

"Republicans this year have said all along we'll do what it takes to get Judge Gorsuch the up-or-down vote he deserves, and next week he will be an associate justice on the United States Supreme Court."

But McCain, in a statement that followed the vote, expressed his dismay.

"Today's vote to eliminate the 60-vote threshold on Supreme Court nominations represents a regrettable setback for the institution of the United States Senate," he said. "I fear today's action will irreparably damage the uniqueness of the Senate, and along with it, any hope of restoring meaningful bipartisanship.

"The Democrats' unprecedented, partisan filibuster of the nomination of Judge Gorsuch unfortunately left me with no other choice than to vote to change the rules and allow Judge Gorsuch to be confirmed by a simple majority," he continued. "I did so with great reluctance — not because I have any doubts that Judge Gorsuch will be an excellent Supreme Court justice, but because of the further damage, perhaps permanent, I fear it will do to the Senate."