WASHINGTON -- When the Senate convenes this morning, it will be for the 25th consecutive day, the second longest streak of all time, and the second time in history the body will cast a vote on Christmas Eve.

The scheduled final vote on the Democrats' health care reform bill around 7 a.m. will cap a frenzied and fractious debate that has seen votes at sunrise, after midnight and everywhere in between. It has tested the patience, nerves and stamina of senators and their staffs as the sessions have stretched into a time of year when, typically, lawmakers have long abandoned the Capitol.

A storm that dropped nearly 2 feet of snow last weekend -- in a town where 2 inches causes a panic -- added to logistical woes, but the Senate continued to press forward on the health insurance overhaul that likely will pass on a strictly party-line vote today after the Senate finished the last of its procedural votes yesterday.

"I think part of it is when you're confined in close quarters with 99 of your closest friends for an extended period of time and you're debating issues on which there's fierce disagreement, it's only natural that people will get a little bit weary," said Sen. John Thune, R-S.D. "And I think tempers fray a little bit."

On Sunday, Sen. Sheldon Whitehouse, D-R.I., drew Republican ire for a fire-and-brimstone floor speech that warned of a "day of reckoning" for foes of the bill.

Sen. Tom Coburn, R-Okla., then caused Democratic outrage by asking colleagues to pray that one of the bill's supporters not show up for the vote, which Democrats interpreted as wishing ill on a member like 92-year-old Sen. Robert Byrd, D-W.Va., who has been ailing but nonetheless has cast crucial votes after arriving at the Capitol in a wheelchair.

When Republicans forced Mr. Byrd to come in for a 1 a.m. roll call, on which his vote turned out to be needless, Sen. Arlen Specter, D-Pa., called it "a new low in the record of the Senate."

Mr. Specter said in his personal experience and historical study, the Senate is now in the most bitter period of partisanship since a senator was attacked with a cane on the floor during a debate in the Civil War era.

Pennsylvania's longest-serving senator, who's running for a sixth term next year, left the Republican Party in April and blamed his former colleagues for being too partisan.

"On the Republican side nobody would speak up against that attitude," he said. "I did, much to my political disadvantage. And now, no one will do it."

Each party blamed the other for the inconvenience of late-night and weekend sessions during the holiday season.

Republicans used a slew of legislative delay tactics -- including on the typically bipartisan defense appropriations bill -- even after it became clear that Democrats had the 60 votes they needed to pass health care.

Yet Majority Leader Harry Reid, of Nevada, held to his Christmas deadline to vote on the bill, which Republicans claimed was an attempt to ram a bill through that wasn't properly vetted by the Senate and the American people.

"So we're going to continue to read and expose the details of the bill that have not actually gotten as much attention in the early stages," said Republican Leader Mitch McConnell, of Kentucky.

"We'll be here until Christmas Eve completing the work on this bill, and I think it's important that we take the time to analyze it in every way we can before the final votes are taken in the Senate."

If the Republicans had used all of their allotted debate time, they could have forced a vote this evening, but because everyone wants to skip town, Mr. McConnell and Mr. Reid struck a deal to vote this morning on health care and to temporarily raise the nation's borrowing limit.

For the record, the only other time the Senate was in session on Christmas Eve was in 1895, when members were debating a military affairs bill on the possible employment of former Confederate officers. The longest continuous Senate session, 26 days, occurred in February and March of 1917, during the run-up to World War I.

The week's deal will allow senators to be home by Christmas, though Sen. Bob Casey Jr., D-Pa., sneaked in some family time Sunday, when he drove home to Scranton in between votes so he could spend two hours with his four daughters -- who range from seventh grade to college age.

Mr. Casey said he arrived just in time to help his oldest daughter unload her belongings from a moving truck and have some quick family time before racing back for a 1 a.m. vote.

Though he acknowledged some fatigue, Mr. Casey did not complain about the schedule, saying that others have much tougher lives.

Mr. Specter, too, said he wasn't particularly concerned about the extended session, and he didn't think it has led to any more bickering than has been the norm this year.

"People are in pretty good spirits considering we haven't been home in weeks and we've been working around the clock," he said.

"People are in fair cheer. The comments on the Senate floor? I haven't seen anybody blow up, let me put it that way. ... It's a great privilege to be a senator, even under these circumstances."

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