Washington (CNN) - Hours of non-stop voting is underway in the Senate that could last until the wee hours of Saturday morning as lawmakers consider dozens of amendments to a Democratic budget proposal.
The "vote-a-rama," as it's known on Capitol Hill, typically is an annual affair each budget season. However, because this is the first formal budget Senate Democrats have put on the floor in four years, almost half the current senators haven't been through the demanding and exhaustive practice that is the result of an open-ended amendment process.
The budget itself is a non-binding blueprint for 2014 that is supposed to set the funding levels for the various government agencies. But because those amounts were set already as part of last year's debt ceiling agreement, this year's budget is really a political document that outlines priorities for the Democrats who control the Senate.
Authored by Senate Budget Committee Chairman Patty Murray, D-Washington, the proposal increases government spending – including repealing the automatic spending cuts required by sequestration – and raises taxes on the wealthy. While it reduces the deficit over 10 years, it stands in sharp contrast to the House budget, written by Rep. Paul Ryan, R-Wisconsin, that passed the House Wednesday. The Ryan plan slashes trillions of dollars from government accounts and balances the budget in just 10 years.
In some years the House and Senate budgets are reconciled, however, that is not expected to happen this year.
"The budget we're debating this week puts our middle class families first," Murray said. "It reflects our pro-growth, pro-middle class agenda that the American people went to the polls in support of just a few months ago."
The top Republican on the Senate Budget Committee disagreed.
"Our chair says this is a pro-growth, pro-middle class budget. I say it's a pro-tax, pro-spend, pro-debt budget," said Sen. Jeff Sessions, R-Alabama. "It's a budget that comes nowhere near doing the things necessary to put America on a sound path."
While Democratic leaders are confident the bill will pass, there are several moderate Democrats, including some up for re-election, who are concerned about the steep tax hikes in the bill and may vote against it.
"Were going to have lots of votes today," Senate Majority Leader Harry Reid, D-Nevada, warned Friday morning. "Everybody is going to be tired."
Reid said 400 amendments had been filed although he said most years between 25 and 35 are voted on during these extended voting sessions. Each vote takes about 15 minutes to complete.
Some of the amendments are designed to put a political squeeze on members of the opposite party. For instance, on Thursday night, Murray offered up Ryan's budget for a vote, forcing Senate Republicans to say whether they are for or against the deep spending cuts and entitlement changes in his plan that Democrats argue are destructive and unrealistic.
For his part, Sessions offered an amendment to require Democrats to present a budget that balances in 10 years – something Murray's budget doesn't do and President Obama's is not expected to do when he unveils his soon.
Democrats and Republicans came together on one amendment that passed overwhelmingly. It would strip from Obamacare a tax on medical devices that has been unpopular since it was created.
Other amendments will deal with a range of social and economic issues from raising or slashing taxes, preserving insurance coverage for contraception, and hiring veterans. Democratic Sen. Chuck Schumer of New York and Republican Sen. Lisa Murkowski of Alaska said they will offer an amendment to block the TSA from allowing small knives on airplanes.
This year, senators have an extra personal incentive to pass a budget. That's because of a new "no budget, no pay" provision that says if a budget is not passed by April 15, senators salaries will be held in escrow until a budget is approved.
While all the Republican and possibly a handful of Democrats will vote against the proposal, a budget is expected to pass - even if it takes until the middle of the night.