Republicans in the U.S. Senate voted to change the rules of the body Thursday when they passed the "nuclear option," eliminating the possibility of filibustering Supreme Court nominees.
The move came after Democrats voted not to end their filibuster on the nomination of Judge Neil Gorsuch to the U.S. Supreme Court.
On a 55-45 vote, Democrats defeated a measure for cloture, a procedure that ends debate on a topic or a nominee. If Democrats had not voted against cloture, the path would have been cleared for Gorsuch's nomination to move on to the Senate for a confirmation vote. Since it failed, the door was left open to hold up the nomination by continuing the filibuster.
Three Democrats, Joe Manchin of West Virginia, Heidi Heitkamp of North Dakota and Joe Donnelly of Indiana, joined Republicans in the effort to avoid the "nuclear option" and move the nomination to the floor where a simple majority vote would put Gorsuch on the nation's highest court.
Senate Majority Leader Mitch McConnell, (Kentucky), had promised Democratic colleagues Thursday morning that he would move to change Senate rules if they did not vote to end the filibuster. 
After the cloture vote failed, McConnell addressed the Senate president on a point of order. He suggested that the vote to end debate on U.S. Supreme Court nominees should be a simple majority vote of the Senate – 51 votes – instead of the 60-vote threshold that had been needed.
McConnell's point of order was overruled, but he appealed the ruling and won on a 52-48 party line vote.
The new rule changes the 60-vote threshold needed to end debate on a Supreme Court nominee to a simple majority to kill a filibuster. That means that if 51 senators say the debate on a candidate is over, then the nomination vote can no longer be delayed.
Currently, there are 52 Republicans in the Senate. 
A final vote on Gorsuch's confirmation is expected for Friday evening. If confirmed, Gorsuch will fill the seat of the late justice Antonin Scalia.