Roll Call has a big story suggesting Harry Reid has concluded that the quest for GOP cooperation is fruitless:

Senate Majority Leader Harry Reid (D-Nev.) on Tuesday strongly urged Finance Chairman Max Baucus (D-Mont.) to drop a proposal to tax health benefits and stop chasing Republican votes on a massive health care reform bill.

Reid, whose leadership is considered crucial if President Barack Obama is to deliver on his promise of enacting health care reform this year, offered the directive to Baucus through an intermediary after consulting with Senate Democratic leaders during Tuesday morning’s regularly scheduled leadership meeting. Baucus met with Finance ranking member Chuck Grassley (R-Iowa) on Tuesday afternoon to relay the information.

According to Democratic sources, Reid told Baucus that taxing health benefits and failing to include a strong government-run insurance option of some sort in his bill would cost 10 to 15 Democratic votes; Reid told Baucus that several in the Conference had serious concerns and that it wasn’t worth securing the support of Grassley and at best a few additional Republicans.

Meanwhile, Josh Marshall's source sees the same thing happening:

From a knowledgeable source on the Hill ...

Now that they have 60, Reid and Durbin need to remind Dem members that when your Leader files cloture, you support him. If you want political cover, vote against final passage. Fine. But opposing cloture means you're supporting a filibuster of your party's agenda.

From what I hear, they started delivering that message, if a softer version of it, earlier today.

Hard to tell what's going on, but GOP support seems even harder to come by than it was for the stimulus, so I can easily see the endgame being a 60-40 vote to stop a filibuster, followed by a smaller margin to pass the bill itself.

--Jonathan Chait