NO must that they vote.
They have the right not to.
They cannot consent without voting, and Advice and Consent are not optional. If they are then Obama doesn't need the Senate at all...
They don't have to vote that is their right as the Senate.
Then Obama has to pick another nomination. This could go back and forth until the next President comes in.
Voting is their Constitutional duty, kids. And if they don't, say goodbye to the GOP Senate. They were going to lose it anyway but pulling this craps means it's gone, gone, gone...