In order to win passage of the Senate bill, House leaders probably would need to agree to make changes later. Those changes would be crafted into a budget reconciliation bill, which would need just 51 votes to pass the Senate. But budget reconciliation bills can only relate to items that involve spending -- not issues such as abortion, on which some House Democrats want tougher provisions than the Senate approved.

Can't Congress just start over?

In theory, yes. But getting a brand-new bill through the Senate without sparking a Republican filibuster might be impossible. Obama has suggested that Congress could craft a bill around the items "that people agree on," but the idea of refusing to compromise was key to Brown's victory in Massachusetts. Many analysts doubt Republicans would abandon what looks like a winning strategy.

Is politics the only obstacle to just passing what "people agree on"?

Not really. It's almost impossible to isolate and approve one provision by itself. The healthcare system is so interconnected that changing one part affects other parts. That leads to consequences and pushes the debate into areas where not everyone agrees. That's why getting a scaled-down bill through Congress is harder than it sounds.

So it seems like it's all over?

Maybe not. Democrats have invested a lot in the healthcare overhaul effort. On reflection, they may conclude that the cost of outright failure would be too high, which would make compromises possible. Besides, voters may decide that the status quo will be expensive for them too.