how many votes are need to pass a bill in the senate
Nuclear option The nuclear option is a parliamentary procedure that allows the United States Senate to override a rule or precedent by a simple majority of 51 votes, instead of by a supermajority of 60 votes. The option is invoked by the presiding officer of the body ruling that the validity of a Senate rule or precedent is a constitutional question. The issue is immediately put to the full Senate, which decides by majority vote. The procedure thus allows the Senate to decide any issue by majority vote, regardless of existing procedural rules, such as current Senate rules specifying that ending a filibuster requires the consent of 60 senators (out of 100) for legislation, and 67 for amending a Senate rule. The term "nuclear option" is an analogy to nuclear weapons being the most extreme option in warfare.
Filibuster in the United States Senate In 1975, the Senate revised its cloture rule so that three-fifths of sworn senators (60 votes out of 100) could limit debate, except for changing Senate rules which still requires a two-thirds majority of those present and voting to invoke cloture.[34][35] However, by returning to an absolute number of all Senators (60) rather than a proportion of those present and voting, the change also made any filibusters easier to sustain on the floor by a small number of senators from the minority party without requiring the presence of their minority colleagues. This further reduced the majority's leverage to force an issue through extended debate.