The Senate is on course for a final vote on health care reform legislation Christmas day -- either gift-wrapping passage of President Obama's top domestic agenda item or sending him the legislative equivalent of a lump of coal.
Getting to that point, however, will be no holiday.
Numerous Senate aides tell Fox News that the expected schedule through next week includes votes on a defense spending bill and an increase in the federal debt limit, some late-night sessions, the introduction of amendments that could take hours to be read aloud and three potentially decisive procedural votes requiring large majorities.
If the Democratic caucus can remain unified that long, it could set up a final vote next Friday on legislation intended to overhaul the health care system, check rising costs, and provided coverage to millions of uninsured Americans.
The year-end wrangling even has staff members and some lawmakers muttering "Harry Christmas," the Associated Press reported.
Senate Majority Leader Harry Reid has struggled to herd and to hold the 60 votes required to advance the health care overhaul that could affect every single American -- not to mention the 2010 midterm elections.
Bickering and general snappishness have bubbled over matters big and small, from policy to floor procedure and now, the prospect of negotiating the massive health care bill through Christmas Eve. (Four years ago, it was "Merry Fristmas," when Republican Leader Bill Frist kept the Senate in sullen session through the holidays.)
Anything can happen in the Senate, where vote timelines are a notoriously unpredictable moving target. But legislative aides provided some guidelines for following the action on the Senate floor:
Friday -- The House passed a defense spending bill Wednesday, sending the legislation to the Senate. A cloture vote, requiring 60 to pass, is expected to take place Friday, which would set the defense bill up for final passage Saturday.
Saturday -- Reid then would introduce what is known as a manager's amendment tied to health care reform, and some Republicans are planning to insist it be read aloud, estimated to take more than 10 hours. That would allow Reid to file motions for three separate cloture votes related to the health care legislation, with a 30-hour wait before each vote.
Tuesday -- After a day of speeches on Monday, the Senate would be set for its first health care cloture vote, possibly as early as 1 a.m. It would be a key test vote to confirm whether the Democratic leaders have enough votes to pass the bill.
Dec. 25 -- After two more cloture votes spaced at least 30 hours apart, the Senate would be ready in the evening on Christmas for a final vote on the bill, though the Senate also would have to fit in a vote on a bill raising the debt ceiling by $290 billion, which the House passed Wednesday.
Senate passage of the health care legislation would be a major victory for Obama's agenda, though the House and Senate still would have to work out the differences between their two bills before final legislation could be approved and sent to Obama's desk for a signature.
When that might happen is anyone's guess.
Fox News' Trish Turner and The Associated Press contributed to this report.