While I personally favor most of those Democratic amendments that are being defeated, the compromise is worth supporting, if it could actually become law. But the end-game that will come into play if the Senate passes a bill obviously involves an additional compromise between the Senate and House approaches.
By refusing to sign on to a smooth-groove path for the compromise absent some assurances about the end-game, Senate Democratic Leader Harry Reid ultimately secured an agreement to cut Democrats, and members of the responsible bipartisan majority of the Judiciary Committee, into the conference committee. That's why there are enough Senate Democrats willing to keep the compromise alive.
This is a song Ed's been singing for years -- we'd better take this deal because it's the best the Republicans will offer us.
But it is defeatist rhetoric and it's wrong. The Democrats face a weakened and divided Republican majority. They needn't take everything they're offered. And they shouldn't.