NUMBERS

The Senate likes to defeat Supreme Court nominations without an "up or down vote," when it does in fact defeat them.

Let me add some numbers, from Supreme Court nominations, that can help highlight this aspect of the nominations battles. (I don't have lower court nominations numbers right now.)

There have been 147 nominations to the Supreme Court. 27 of them have been rejected. Of those 27, 12 were defeated by an "up or down vote." 4 were indefinitely postponed by the Senate, 6 were withdrawn, and 5 died due to Senate inaction. In other words, one way of looking at these numbers is that in those nominations that were controversial enough to be defeated by opposition in the Senate, less than half were defeated by an "up or down vote." And this isn't even counting those nominations that the President would have liked to have sent to the Senate, but refrained from submitting because of expected Senate opposition.

A filibuster strikes me as just as legitimate as other means of defeating judicial nominations, especially since I am willing to be as realist with respect to constitutional requirements on Senate rules as Republicans apparently are with respect to TPA.

The idea of a requirement for an "up or down vote" is too narrow to account for Senate practice, and too entangled with current partisan battles to be discussed in a dispassionate fashion by most participants in the dispute.

Source for the numbers and an interesting article: P. S. Ruckman, Jr. "The Supreme Court, Critical Nominations, and the Senate Confirmation Process." The Journal of Politics, Vol. 55, No. 3. (Aug., 1993), pp. 793-805.
Link, if you've got JSTOR

MORE: Above, I'm not as clear as I should be: the nominations died due to Senate inaction, not the nominees.