Ed Kilgore crunches the numbers and finds that Pelosi and Reid managed to hold the caucus together pretty well:
47 House Democrats represent districts carried by John McCain in a bad Republican year. They voted 34-13 for the Obama-backed budget. 13 Democratic senators represent states carried by McCain; they voted for the budget 10-3.
Of the four House Democrats voting against the budget who represent districts carried by Obama, three (Barrow of GA, Foster of IL, and Nye of VA) are from seats recently won by Republicans, and the fourth is Dennis Kucinich. Only two Senate Democrats from states won by Obama voted against the budget: Arlen Specter, who switched parties the day of the vote, and Evan Bayh, from a state that narrowly went Democratic for the first time in 44 years (true also, of course, for Virginia senators Warner and Webb, who voted for the budget).
Looking at the Democratic groupings often suspected of disloyalty is interesting, too. The Blue Dog Coalition in the House voted for the budget by a 41-6 margin. And in the Senate, the 15 Democrats whose names have most often been associated with the "moderate working group" led by Evan Bayh split 13-2 in favor of the budget.
All in all, not that bad a day for party unity.