This made passing legislation very much harder. The decisions Democrats made on health care policy in early 2009 ruled out the possibility of significant Republican support. You can pass popular legislation on party-line votes, and you usually get some support from the other side, even if unsolicited. This was the case on Medicare in 1965, for example.
But it's hard to pass unpopular legislation on party-line votes. Take the example of the Troubled Asset Relief Program in fall 2008. Bailing out banks was obviously not going to be popular (the 2008 exit poll shows voters opposed by 56 percent to 39 percent). It was easy to imagine opponents running negative ads in the next campaign. TARP was passed, after one misfire in the House, by bipartisan coalitions of members of both parties with safe seats. Members of both parties with vulnerable seats, with only a few exceptions, were left to protect themselves by voting against it.
In fall 2009, Democrats could have pivoted on health care to craft a popular bill or a watered-down unpopular bill to be passed by a bipartisan safe-seat coalition. Instead, they plunged ahead and rammed through unpopular bills on party-line votes.
Pelosi got a 220-215 margin in the House in November after accepting an amendment by Rep. Bart Stupak that banned funding of abortions.
In the Senate in December, Majority Leader Harry Reid predictably had to pay a high price -- the Cornhusker kickback and the Louisiana purchase -- for the 59th and 60th votes. That's always the case when you need 60 out of 60.
Scott Brown's election in January in Massachusetts deprived Reid of his 60th vote. The only way forward for the Democrats is for the House to pass the Senate bill and then trust the Senate to fix it through the reconciliation process. Pelosi has had six weeks to get the votes for that and hasn't done so yet.
It's beginning to look like the goal of health care legislation was a bridge too far. There's a reason it's hard to pass unpopular legislation on party-line votes. It's not the Senate rules. It's called democracy.