Democrats in the U.S. Senate have invoked the "nuclear option" by changing the rules to require a mere majority, instead of 60 votes, to proceed with debate on executive branch appointees other than U.S. Supreme Court justices, without obtaining the usually required two-thirds majority vote necessary to change Senate rules. "The vote to change the rule passed 52 to 48. Three Democrats — Sens. Carl Levin (Mich.), Joe Manchin III (W.Va.) and Mark Pryor (Ark.) — joined 45 Republicans in opposing the measure."
Other obscure Senate rules that can be used to block nominations were also swept away.
The U.S. House of Representatives adopts new rules from scratch every two years by majority vote and does not require super-majorities for legislative action.
But, the filibuster has been interpreted since the Civil Rights era to require sixty vote supermajorities to pass almost all kinds of legislation and all nominations in the U.S. Senate with filibusters and related arcane rules. In recent years, Republicans have increasingly used these powers to thwart Democratic Party majorities in the U.S. Senate.
Historically, the U.S. Senate has considered itself a "continuous body" since only one-third of its members face election every two years, and hence there has never been a clean slate point at which new Senate rules can be adopted by majority vote as they are in the U.S. House.
But, the illegitimacy of Republican's routine use of the tactic to block nominees ultimately came to appear worse than hoary old Senate traditions. The change, which amounts to a virtual amendment of the constitution, has provoked surprisingly little outrage, even among Republicans, who warn that turnabout is fair play, rather than crying bloody murder.