The Senate filibuster is a procedural rule that allows any senator to extend debate indefinitely on a bill, effectively blocking a vote unless 60 of 100 senators agree to end debate — a process called cloture. It was not in the original Constitution but evolved through Senate precedent. Because Republicans hold 53 seats, they need 7 Democratic votes to break a filibuster. Senate Majority Leader John Thune has refused to eliminate the filibuster rule, creating an impasse on the SAVE America Act.