During a time when the nation will need a lot of legislation quickly, it seems absurd that the Senate binds itself to an obsolete supermajority rule requiring 60 votes to end a filibuster and force a vote. What's so magic about the number 60? Why should 41 senators -- coincidentally the current number of Republicans -- be able to block public policy indefinitely?
It's not because the Constitution requires it. It's because of Senate Rule 22 on cloture, adopted in 1917 and changed in 1975 (requiring a three-fifths vote instead of two-thirds) -- and it's merely a Senate tradition. (In contrast, the House, which originally also practiced filibusters, found them cumbersome and, by 1842, eliminated them.)
Once the Senate has a quorum, a majority vote on any issue carries the day, with five exceptions enumerated in the Constitution: impeachment, expulsion of members, veto overrides, confirmation of treaties and constitutional amendments. Otherwise, all that the Constitution tells the Senate is that it is free to make up its own rules.
However, the Senate has its reasons for keeping a supermajority requirement, and here are two they will say out loud: It preserves fellowship among the senators, and delayed legislation often results in improved legislation.