Republican attempts to scuttle the nonbinding timeline failed, 50-48, largely along party lines.
President Bush is said to be "disappointed" by the Senate vote, reports CBS News White House correspondent Mark Knoller, but White House spokeswoman Dana Perino says the measure's timeline for withdrawal from Iraq has no chance of becoming law – because if the bill ever reaches Mr. Bush's desk, he'll veto it.
The vote marked the Senate's most forceful challenge to date of the administration's handling of a war that has claimed the lives of more than 3,200 U.S. troops. It came days after the House approved a binding withdrawal deadline of Sept. 1, 2008, and increased the likelihood of a veto confrontation this spring.
After weeks of setbacks on the Senate floor, Majority Leader Harry Reid said the moment was at hand to "send a message to President Bush that the time has come to find a new way forward in this intractable war."
"It is a choice between staying the course in Iraq or changing the course in Iraq," he said.
But Republicans — and Sen. Joseph Lieberman, an independent Democrat — argued otherwise.
Sen. John McCain, R-Ariz., a presidential hopeful, said "we are starting to turn things around" in the Iraq war, and added that critics "conceive no failure as worse than remaining in Iraq and no success worthy of additional sacrifice. They are wrong."
Similar legislation drew only 48 votes in the Senate earlier this month, but Democratic leaders made a change that persuaded Nebraska's Democratic Sen. Ben Nelson to swing behind the measure.
Additionally, GOP Sens. Chuck Hagel of Nebraska and Gordon Smith of Oregon sided with the Democrats, assuring them of the majority they needed to turn back a challenge led by Sen. Thad Cochran, R-Miss. "The president's strategy is taking America deeper and deeper into this quagmire with no exit strategy," said Hagel, the most vocal Republican critic of the war in Congress.
Vice President Dick Cheney traveled to the Capitol in case his vote was needed to break a tie, a measure of the importance the administration places on the issue.
The debate came on legislation that provides $122 billion to fund the wars in Iraq and Afghanistan as well as domestic priorities such relief to hurricane victims and payments to farmers. Final passage is expected Wednesday or Thursday.
Separately, a minimum wage increase was attached to the spending bill without controversy, along with companion tax cuts that the Republicans have demanded as the price for their support of the increase in the federal wage floor. The House and Senate have passed different versions of the minimum wage-tax package, but they have yet to reach a compromise.
The House has already passed legislation requiring troops to be withdrawn by Sept. 1, 2008. The Senate vote assured that the Democratic-controlled Congress would send Bush legislation later this spring that calls for a change in war policy. A veto appears to be a certainty.
That would put the onus back on the Democrats, who would have to decide how long they wanted to extend the test of wills in the face of what are likely to be increasingly urgent statements from the administration that the money is needed for troops in the war zone.
"I hope he will work with us so we can come up with something agreeable for both" sides, Reid said at a post-vote news conference. "But I'm not anxious to strip anything out of the bill."
As drafted, the legislation requires a troop withdrawal to begin within 120 days, with a nonbinding goal that calls for the combat troops to be gone within a year.
The measure also includes a series of suggested goals for the Iraqi government to meet to provide for its own security, enhance democracy and distribute its oil wealth fairly — provisions designed to attract support from Nelson and Sen. Mark Pryor of Arkansas.
Despite the change, Pryor voted with Republicans, saying he would only support a timeline if the date were secret.
The vote was a critical test for Reid and the new Democratic majority in the Senate nearly three months after they took power. Despite several attempts, they had yet to win approval for any legislation challenging Bush's policies.
Republicans prevented debate over the winter on nonbinding measures critical of Bush's decision to deploy an additional 21,500 troops. That led to the 50-48 vote derailing of a bill that called for a troop withdrawal to begin within 120 days but set only a nonbinding target of March 31, 2008, for the departure of the final combat forces.
Some Democrats said they would support the nonbinding timetable even though they wanted more. "I want a deadline not only for commencing the withdrawal of our forces but also completing it rather than a target date," said Sen. Patrick Leahy, D-Vt.
"This provision represents a 90-degree change of course from the president's policy of escalation in the middle of a civil war," he said. "I'm confident once the withdrawal of our troops begins there will be no turning back."
Lieberman, who won a new term last fall in a three-way race after losing the Democratic nomination to an anti-war insurgent, depicted the vote as a turning point. He said the effect of the timeline would be to "snatch defeat from the jaws of progress in Iraq."