According to this, the authors of our Constitution initially wanted to require a 2/3s vote of the Senate to REJECT a judicial nominee. Why? Because judges are supposed to be appointed by the Executive Branch. The dems have decided to go against this and make it so that judges are really appointed by them, with the President's appointment only a formality, as they will block any judges they don't like. Despite the fact that the Constitution does say 1/2 to approve, the Dems are using the filibuster, a concept not even once mentioned in the Constitution, to make it 3/5s to approve a judge. They have, in all reality, stolen a power of the Executive Branch and thrown off the system of checks and balances.