Senator Sheldon Whitehouse (D-RI) puts, in better terms than I could, why some form of health care legislation has to pass. As he says, "When it turns out there are no death panels, when there is no bureaucrat between you and your doctor, when the ways your health care changes seem like a good deal to you, and a pretty smart idea, when the American public sees the discrepancy between what really is, and what they were told by the Republicans, there will be a reckoning. There will come a day of judgment about who was telling the truth."
The Senate Dems have passed the cloture vote now. They just have to pass the bill, which is a foregone conclusion at this point, then send it to conference, which is where it gets tricky. I generally side with the progressives on the substance of the bill, but with the realists on the necessity of passing some bill, however imperfect, rather than no bill in the quest for perfection.
You can read the Hofstadter essay that Whitehouse quotes from in full here.