WASHINGTON (AP) — An exhausted Senate gave pre-dawn approval today to a Democratic $3.7 trillion budget for next year that embraces nearly $1 trillion in tax increases over the coming decade but shelters domestic programs targeted for cuts by House Republicans.

While their victory was by a razor-thin 50-49, the vote let Democrats tout their priorities. Yet it doesn't resolve the deep differences the two parties have over deficits and the size of government.

Joining all Republicans voting no were four Democrats who face re-election next year in potentially difficult races: Sens. Max Baucus of Montana, Mark Begich of Alaska, Kay Hagan of North Carolina and Mark Pryor of Arkansas. Sen. Frank Lautenberg, D-N.J., did not vote.

The vote came after lawmakers labored through the night on scores of symbolic amendments, ranging from voicing support for letting states collect taxes on Internet sales to expressing opposition to requiring photo ID's for voters.

The Senate's budget would shrink annual federal shortfalls over the next decade to nearly $400 billion, raise unspecified taxes by $975 billion and cull modest savings from domestic programs.

In contrast, a rival budget approved by the GOP-run House balances the budget within 10 years without boosting taxes.

That blueprint— by House Budget Committee Chairman Paul Ryan, R-Wis., his party's vice presidential candidate last year — claims $4 trillion more in savings over the period than Senate Democrats by digging deeply into Medicaid, food stamps and other safety net programs for the needy. It would also transform the Medicare health care program for seniors into a voucher-like system for future recipients.

"We have presented very different visions for how our country should work and who it should work for," said Sen. Patty Murray, D-Wash., who chairs the Senate Budget Committee. "But I am hopeful that we can bridge this divide."

A day that stretched roughly 20 hours featured brittle debate at times. The loudest moment came toward the end, when senators rose as one to cheer a handful of Senate pages — high school students — who lawmakers said had worked in the chamber since the morning's opening gavel. Senators then left town for a two-week spring recess.

Congressional budgets are planning documents that leave actual changes in revenues and spending for later legislation, and this was the first the Democratic-run Senate has approved in four years. That lapse is testament to the political and mathematical contortions needed to write fiscal plans in an era of record-breaking deficits that until this year exceeded an eye-popping $1 trillion annually, and to the parties' profoundly conflicting views.

"I believe we're in denial about the financial condition of our country," Sen. Jeff Sessions of Alabama, top Republican on the Budget panel, said of Democratic efforts to boost spending on some programs. "Trust me, we've got to have some spending reductions."

Though budget shortfalls have shown signs of easing slightly and temporarily, there is no easy path for the two parties to find compromise — which the first months of 2013 have amply illustrated.

Already this year, Congress has raised taxes on the rich after narrowly averting tax boosts on virtually everyone else, tolerated $85 billion in automatic spending cuts, temporarily sidestepped a federal default and prevented a potential government shutdown.