US senators eager to head home for the congressional recess on Friday launched what could become a legislative all-nighter -- a rare, free-wheeling session known as a "vote-a-rama."
For the first time in four years, the 100 members of the Senate will pack the chamber for 10 hours or more, beginning at 3:00 pm Friday, for dozens of back-to-back votes on amendments to the Senate's pending budget resolution.
Because of a quirk of Senate rules peculiar to the budget, lawmakers may offer an unlimited number of amendments to the fiscal blueprint between the end of debate and the vote itself.
More than 400 amendments have been filed, according to Democratic Senate Majority Leader Harry Reid, who called the vote-a-rama in order to get the 2014 budget done and dusted before the two-week recess.
"Everyone's going to be tired," Reid warned fellow members.
The amendments need not be related to budget matters, and most will fall by the wayside, either withdrawn by their sponsors after negotiations or folded into other amendments.
But some will carry a political sting that could be used against lawmakers later if and when they vote against them.
Republican Richard Burr, for instance, introduced a measure to repeal what he describes as the $1 trillion tax resulting from President Barack Obama's healthcare law.
The move will fail, but Republicans will use such "no" votes to tar Democrats as tax-and-spend liberals.
Other measures seek to cut off US aid to Pakistan, push for tighter gun laws, forbid drone killings of Americans on US soil, or bar unemployment compensation for millionaires.
It all has a few senators in highly partisan Washington grumbling.
"It's been a long four years without vote-a-rama. I can't wait," Senate Minority Leader Mitch McConnell deadpanned to AFP.
Democrat Mark Warner used more colorful language to highlight the necessary-but-painful nature of the exercise. "It's a little bit like an enema," he whispered.
Senate leadership told members to expect 35 or more votes Friday, in a session that could run well past midnight.
"We have a busy day ahead of us," said Patty Murray, the senator who unveiled the Democratic budget plan and who will preside over much of the debate.
Time discipline will be key. Debate between votes will be held to as little as 30 seconds per side, a lightning pace given the deliberative nature of the Senate.
The first amendment under consideration, a measure to boost wildfire suppression efforts by $100 million, was dispensed with in 90 seconds.
When some lawmakers began to wander off after the third vote, Murray reined them in. "You leave at your own peril," she warned.
A third of the senators have never experienced the free-for-all, which last took place in 2009, the most recent year Obama's Democrats tabled a budget.
One of the newcomers is Senator John Boozman, who said he was filling his pockets with granola bars and looked forward to jumping into the legislative scrum. But he and others will need to be on their toes.
"These things come up very rapidly, and it does really force you to think about some issues that you hadn't thought about much," he said.
Veteran Republican John McCain, who has seen his fair share of vote-a-ramas, dismissed the event as a "charade."
"It has zero impact on anybody, especially now, when everybody knows that the House and the Senate budgets will never reconcile," he argued.
The House on Thursday has passed its own plan which aims to balance the budget in 10 years by slashing spending, reforming entitlements and repealing "Obamacare." The Senate voted down the House budget the same day.
Murray's Democratic alternative includes a combination of targeted spending cuts and new tax revenue.
Neither budget is expected to pass the full Congress.