Washington (CNN) - The Democrat-controlled Senate passed its first formal budget proposal in four years early Saturday after hours of non-stop voting that started Friday evening.
The non-binding plan for the 2014 budget calls for a trillion dollars in tax increases and passed 50 to 49. No Republicans voted for the bill, and four Democrats voted against it.
It now goes to the House, where it is expected to be shot down. Senators recently voted down a budget proposal passed by the Republican-controlled house.
The two budget proposals and a third one to be offered by the president will likely be used as a basis for future negotiations between the parties.
The Senate convened on Friday morning, and voting started about 4 p.m. ET, as lawmakers considered dozens of amendments to the Democratic budget proposal.
The "vote-a-rama," as it's known on Capitol Hill, typically is an annual affair each budget season. However, because it's been so long since Democrats put a budget on the floor, almost half the current senators had not been through the demanding and exhaustive practice. It involves the consideration of and voting on dozens of amendments to the proposed bill.
The process took 13 hours and ended just before 5:00 a.m. Saturday.
As voting on final passage of the bill began, Senate Minority Leader Mitch McConnell called the session "one of the Senate's finest days in recent history."
"I commend everyone who has participated in this extraordinary debate," McConnell said.
The proposal is supposed to set the funding levels for the various government agencies next year. 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 Budget Committee Chairwoman 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 proposal, 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 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 were confident the Senate bill would pass, there were several moderate Democrats, including some up for re-election, who were concerned about the steep tax hikes in it and indicated they might vote against it.
In the end, Senators Max Baucus, D-Montana, Mark Begich, D-Alaska, Kay Hagan, D-North Carolina and Mark Pryor, D-Arkansas voted against the budget proposal.
"Were going to have lots of votes today," Senate Majority Leader Harry Reid warned Friday morning, going into the session. "Everybody is going to be tired."
Reid said 400 amendments had been filed, but he added that in most years only 25 to 35 are voted on during these extended voting sessions. Each vote takes about 15 minutes to complete.
The amendments are not-binding but still symbolically significant.
This time there were 70 votes for 101 amendments; some measures were agreed to unanimously en bloc after party leaders grouped the amendments together to cut down on time.
Some of the amendments were designed to put a political squeeze on members of the opposite party. For instance, 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. Democrats argue the cuts 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 it soon.
Democrats and Republicans came together on one amendment that passed overwhelmingly. It would strip from the Affordable Health Care Act a tax on medical devices that has been unpopular since it was created.
Other amendments dealt with a range of social and economic issues from raising or slashing taxes, preserving insurance coverage for contraception, hiring veterans, endorsing the Keystone XL pipeline, repealing "Obamacare," and prohibiting illegal immigrants from being eligible for Medicaid and Affordable Health Care Act benefits.
The Keystone amendment, offered by Senators John Hoeven, R-North Dakota, and Max Baucus, D-Montana, passed by a vote of 62 to 37. Though non-binding, the measure establishes the Senate's official support of the controversial project, and is symbolically important as President Obama weighs his decision on whether to approve construction of the pipeline. He is expected to make a final decision sometime this summer.
The Senate also passed - by a vote of 99 to 0 - an amendment put forth by Sen. David Vitter, R-Louisiana, to end so-called "Too Big To Fail" financial advantages for megabanks, defined as any bank that has more that $500 billion in total assets.
"This amendment is very simple. It says we should do away with the federal policies that create that subsidy, that uneven playing field," Vitter said. "It doesn't say it would forcibly break up the banks, it doesn't say we would tax them. It just says that."
This year, senators had an extra personal incentive to pass a budget plan. 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.
That threat is now off the table, though an amendment asking all Senators to donate 20 percent of their own salaries to a charity of their choice did pass by a voice vote.
Republican South Carolina Sen. Lindsey Graham offered the measure so that Senators "would feel what other people are feeling because of the sequestration."
Lawmakers' salaries were not affected by the forced spending cuts that took effect on March 1, because the Constitution requires a new law to be passed in order to alter congressional compensation. Graham's amendment establishes a deficit-neutral reserve fund to broaden the effects of the spending cuts.