From an observer on the Hill …
Note that [Lieberman] says he would vote to proceed to the bill — just not to move to final passage.
There will be several turning points:
1. Cloture vote cutting off debate on the motion to proceed to the health care bill (60 votes);
2. Motion to proceed to the bill (50 votes, may be waived if we get cloture);
3. Amendments to modify the public option piece, e.g. to a trigger (likely requiring 60 votes);
4. Cloture vote to end debate on the bill and move to final passage (60 votes); and
5. Final passage of the bill (50 votes).
Lieberman says that he’ll vote with Leadership through #1 and #2. If the other 59 Dems do so as well, that gets the Senate on to the bill. Once the Senate’s on the bill, it will likely take 60 votes to water down the opt-out, #3 above. And those efforts will occur under the threat by Lieberman, and perhaps others, to deny 60 votes for #4.