Looking forward to tomorrow's health care "summit," Ben Smith of Politico has a pretty good summary of the five distinct audiences the President must think about in handling this event: House Democrats, Senate Democrats, the Public, the Fans of Bipartisanship, and Republicans. But there are obviously priorities in his messaging:

He’ll be making the sale, for the umpteenth time, to an American public that supports aspects of health care legislation but opposes the bill. He’ll be pitching Beltway graybeards obsessed, as always, with bipartisanship. He’ll be appealing to moderate Senate Democrats to back reconciliation.

But most important will be his pitch to a handful of conservative Democrats in the House who will have to switch their votes and vote for the Senate health care bill for it to pass into law.

Smith's right that the most important immediate audience is House Democrats. In the longer run, however, this summit is a very important landmark in his overall positioning of himself and his party for the midterm elections in November. The reality in Washington is that a Republican Party that is becoming more ideologically extreme each day is using every procedural tool and political trick you can imagine to avoid any real action on any significant issue. If that reality becomes more generally known because of the summit, then it will be a success for Obama and Democrats, regardless of how it plays with the Republicans, the pundit class, or Democrats who are wavering on health reform.