Republican Leader Mitch McConnell and his top aides are warning the detonation of the so-called "nuclear option" will backfire on Senate Democrats after the results of next year's election.
The vote gives the 2014 mid-term elections even higher stakes and puts more attention on Kentucky's Senate race, which could pit McConnell up against Democratic challenger Alison Lundergan Grimes next fall.
After months of debating the use of the 60-vote cloture maneuver to block President Obama's judicial nominees and other measures, Democratic Leader Harry Reid moved forward with changing the Senate rules.
By a 52-48 vote, it now takes just a simple majority vote to end debate and move ahead with presidential nominations other than Supreme Court justices.
"If you want to play games and set yet another precedent that you'll no doubt come to regret. I say to my friends on the other side of the aisle you'll regret this," said McConnell. "And you may regret it a lot sooner than you think."
Others in McConnell's camp, such as former chief of staff Josh Holmes, who is working on the senator's re-election bid, also derided the nuclear option. But he put the vote in even starker terms if the GOP captures the majority next fall.