Senate Republicans on Thursday defied Democrats and delivered a big win for President Trump, by voting to change Senate precedent in order to allow the confirmation of Trump's Supreme Court pick.

Senate Majority Leader Mitch McConnell, R-Ky., invoked the so-called "nuclear option" after warning for weeks that he would take that step if Democrats chose to vote down Trump's pick, Judge Neil Gorsuch. Democrats did just that shortly before noon on Thursday, which prompted McConnell to start the process of changing the process for Supreme Court picks.

The change sets a new precedent in the Senate that will allow all Supreme Court nominees to more easily win confirmation by eliminating the 60-vote filibuster, and allowing them to advance with just 51 votes.

Immediately after that vote, the Senate used the new precedent to end debate on Gorsuch with a simple majority vote, 55-45. Three Democrats joined Republicans in that vote, which sets up Gorsuch's confirmation on Friday: Joe Donnelly of Indiana, Heide Heitkamp of North Dakota, and Joe Manchin of West Virginia voted with Republicans to end debate.

McConnell started the process by raising a point of order challenging the current process for confirming Supreme Court nominees. That process required 60 votes to end debate on these nominees, although Democrats changed the process in 2013 by allowing just a simple majority vote for all others.

To make the change, McConnell contested the ruling of the Senate parliamentarian. A vote was called on whether to maintain the ruling of the chair, or to change precedent as proposed by McConnell, and the Senate voted 48-52 against keeping the current process in place. With that vote, Republicans won the battle.

Democrats fought the entire time to delay Republicans, and at one point even called a vote on adjourning until later in the day. But after the vote series, a final vote confirming Gorsuch was expected late Friday afternoon under the new precedent.

McConnell's proposed change would not impact the typically required 60-vote threshold needed to move forward with legislation, although many senators in both parties fear it is now just a matter of time before that precedent is obliterated by the nuclear option.

"Just as it seemed unthinkable decades ago that we would change the rules for nominees, today's vote is a cautionary tale about how unbridled partisan escalation can overwhelm our basic inclination to work together and and frustrate our efforts to pull back, blocking us from steering the ship of the Senate away from the rocks," said Senate Minority Leader Chuck Schumer, D-N.Y. "There's a reason it was dubbed the nuclear option."

Republicans engaged in finger-pointing floor speeches before McConnell started the process of making the change.

The GOP pointed out it was Democrats, not Republicans, who first invoked the nuclear option in November 2013 when then-Majority Leader Harry Reid, D-Nev., lowered the threshold from 60 votes to a simple majority for all executive branch and lower court nominees.

"I know the Democratic leader would rather not revisit the circumstances that brought us to this moment," McConnell said on the Senate floor earlier. "He and his party decided to 'change the ground rules' for handling judicial nominations. He and his party pioneered the practice of filibustering lower court judicial nominees. He and his party launched the first partisan filibuster of a Supreme Court nominee. He and his party deployed the nuclear option in 2013."

Democrats accused the GOP of choosing an ultra-conservative high court nominee, forcing them to vote against Gorsuch.

Republicans argued that Democrats had set the stage for this in 2013, when they similarly invoked the lower threshold for all executive branch and lower court nominees.

Schumer, moments before the change, called on the GOP to sit down with Democrats and President Trump and choose a nominee with bipartisan appeal. But Republicans scoffed at the notion, pointing to the list of liberal court judges who made it to the bench, including Supreme Court Justice Ruth Bader Ginsburg.

"This is the latest escalation in the Left's never-ending judicial war, the most audacious yet, and it cannot, and it will not stand," McConnell said. "There cannot be two sets of standards, one for the nominees of Democratic presidents and another for the nominees of Republican presidents."