Senate Republicans officially changed the chamber's rules on Thursday to allow votes on the appointment of unlimited groups of nominees at once.

Senators voted 53-45 to change the rules with a simple majority instead of 60 votes, a measure known as the “nuclear option.”

The “nuclear option,” which allows the majority party to change the rules with a simple majority vote, is so named because it is considered highly detrimental to the two-party system. In total, the chamber needed four votes Thursday to make the change.

The rules change will allow the Senate to confirm multiple nominations at once, helping clear a backlog of nearly 150 nominees awaiting a floor vote.

And it will also allow the Republican majority in the upper chamber to propose candidates with partisan support in similar groups later.

The rule change will apply only to civilian nominees in the executive branch, not Cabinet members or the judiciary.

Republicans argue it is necessary because Democrats have slowed the confirmation process by forcing time-consuming votes on each nominee, rather than allowing some to be confirmed by faster voice votes.

Democrats have criticized Republicans for invoking the “nuclear option” by using a simple majority to change the chamber’s rules, warning against more controversial and what will happen when Democrats are next in the majority.

“If Republicans go nuclear, the historically bad nominees we’ve seen under President Trump will only get worse,” Senate Democratic Leader Chuck Schumer (D-N.Y.) declared on the floor earlier this week.

“Instead of deliberating, Senate Democrats opted for unprecedented delay. That ends now,”Republican leader John Barrasso (R-Wyoming) said Thursday.