The 51-46 Senate vote was largely along party lines, and like House passage a day earlier it underscored that the war's congressional opponents are far short of the two-thirds majority needed to override a Bush veto.
Democrats marked Thursday's final passage with a news conference during which they repeatedly urged Bush to reconsider his veto threat. "This bill for the first time gives the president of the United States an exit strategy" from Iraq, said Rep. David Obey of Wisconsin.
The legislation is "in keeping with what the American people want," added Senate Majority Leader Harry Reid of Nevada.
The White House was unmoved. "The president's determined to win in Iraq. I think the bill that they sent us today is mission defeated," said deputy press secretary Dana Perino. "This bill is dead before arrival."
Given that standoff, Republicans and Democrats alike already were maneuvering for position on a follow-up bill.
Senate Republican leader Mitch McConnell dismissed the just-passed legislation as "political posturing" by Democrats that deserves the veto it will receive. "The solution is simple: Take out the surrender date, take out the pork and get the funds to our troops," he said.
The bill would provide $124.2 billion, more than $90 billion of which would go for the wars in Iraq and Afghanistan. Democrats added billions more for domestic programs, and while most of the debate focused on the troop withdrawal issue, some of the extra spending also has drawn Bush's criticism.
Meanwhile, in Iraq, bombers struck an Iraqi army post northeast of Baghdad and civilian targets in the city as violence across Iraq killed at least 72 people Thursday, including the bullet-riddled bodies of 27 men dumped in the capital - apparent victims of sectarian death squads.
Still, the top American military spokesman insisted the U.S. command felt "very comfortable" that it is making "steady progress" in restoring order in Baghdad.
"We are seeing those initial signs of progress being made," Maj. Gen. William C. Caldwell told Associated Press Radio.
In reaction to the day's developments in Washington, Iraqi government spokesman Ali al-Dabbagh said Oct. 1 was too soon for a withdrawal to start and criticized the U.S. Senate vote, saying it "sends wrong signals" to armed militants.
The vote occurred nearly four years after Bush stood on the deck of an aircraft carrier before a banner that read "Mission Accomplished" - and 113 days after Democrats took power in Congress and vowed to change course in a war that has cost the lives of more than 3,300 U.S. troops.
During Vietnam, a longer and far deadlier war for U.S. forces, Congress went years before it was able to agree on legislation significantly challenging presidential war policy.
In the current case, any veto override attempt would occur in the House, and Democrats concede they lack the votes to prevail.
With House Speaker Nancy Pelosi at his side, Reid said Democrats hoped to have a follow-up war-funding bill ready for the president's signature by June 1. Despite administration claims to the contrary, he said that was soon enough to prevent serious disruption in military operations.
Several Democratic officials have said they expect the next measure will jettison the withdrawal timetable, a concession to Bush. At the same time, they say they hope to include standards for the Iraqi government to meet on issues such as expanding democratic participation and allocating oil resources.
Bush and congressional Republicans, eager to signal the public that they do not support an open-ended commitment to Iraq, have both embraced these so-called benchmarks. Unlike Democrats, they generally oppose using benchmarks to require specific actions, such as troop withdrawals.
Rep. John Boehner of Ohio, the House Republican leader, said at a news conference that the purpose of benchmarks should be to "see how the Iraqi government is doing," rather than to establish deadlines for a troop withdrawal.
Opinion on the issue covered a wide spectrum. "The only good measure that exists in Iraq now is body counts, and that's not a very good measure," said Sen. Mark Pryor of Arkansas, a moderate Democrat. Congress acted as the top U.S. military commander in Iraq, Gen. David Petraeus, said at a Pentagon news conference that the U.S. mission "may get harder before it gets easier."
Less than three months after Bush announced an increase in troop strength and a shift in tactics, Petraeus said improvements were evident in both Baghdad and the Anbar Province in western Iraq. At the same time, he said the accomplishments "have not come without sacrifice" and that greater American losses have resulted from increased car bombings and suicide attacks, plus the greater concentration of U.S. troops among the Iraqi population.
There were no surprises in the Senate vote, in which 48 Democrats and one independent joined Republicans Gordon Smith of Oregon and Chuck Hagel of Nebraska in supporting the bill. Sen. Joseph Lieberman, a Connecticut independent who typically votes with the Democrats, sided with 45 Republicans in opposition. In a clear warning to the White House, Sen. Susan Collins, R-Maine, opposed the legislation but issued a statement saying her patience with the war was limited. "If the president's new strategy does not demonstrate significant results by August, then Congress should consider all options including a redefinition of our mission and a gradual but significant withdrawal of our troops next year," she said. Like Hagel and Smith, Collins is coming up on a 2008 re-election campaign. Democrats have long argued that Republicans must choose between a politically unpopular war on the one hand and a president of their own party on the other. The legislation requires a troop withdrawal to begin July 1 if Bush cannot certify that the Iraqi government is making progress in disarming militias, reducing sectarian violence and forging political agreements, otherwise by Oct. 1. While the beginning of a withdrawal is mandated, the balance of the pullback is merely advisory, to take place by April 1, 2008. Troops could remain after that date to conduct counterterrorism missions, protect U.S. facilities and personnel and train Iraqi security forces. The war aside, Democrats included more than $10 billion in the legislation that Bush did not ask for. Included was $3.5 billion for the victims of Hurricane Katrina; $2.3 billion for homeland security and smaller amounts for rural schools, firefighting, children's health care and other programs. The violence came as the Democratic-controlled U.S. Senate adopted House-passed legislation calling for U.S. troops to begin leaving Iraq by Oct. 1. President Bush pledged to veto the measure, and neither body passed the measure with enough votes to override a veto. The deadliest attack occurred about 9 a.m. when a suicide car bomber killed 10 Iraqi soldiers at a checkpoint in Khalis, a longtime flashpoint city about 50 miles northeast of Baghdad. Ten other soldiers and five civilians were wounded, police said. The city is in Diyala province, which has seen some of Iraq's worst violence recently. Mostly Sunni Arab insurgents are thought to have fled to the area to escape the security crackdown in Baghdad that U.S. and Iraqi troops launched Feb. 14. In the capital, a car bomb exploded near Baghdad University, killing eight civilians and wounding 19, including some students, police said. Associated Press Television News footage showed an elderly woman screaming, "Oh, my son," as she sobbed beside twisted debris. Ahmed Jassim, who works in a nearby hotel, said he rushed outside after hearing the explosion and helped carry the wounded to ambulances. "The insurgents were surely targeting civilians because there was no military presence in the area," he said. "I saw small pieces of flesh and a small blood pool." Four other civilians were killed and nine wounded when a roadside bomb exploded near a market in central Baghdad, police said. The blast missed its intended target - a passing police patrol. In the city's sprawling Shiite Muslim neighborhood of Sadr City, U.S. troops killed three militants during a gunbattle, the military said. Later in the day, a funeral procession was held in the district for an Iraqi who residents said was killed in the fighting. Two suicide bombers attacked an office of the Kurdistan Democratic Party of Massoud Barzani, leader of the autonomous Kurdish region in northern Iraq. The blasts killed three security guards and wounded five, police said. Casualties could have been worse if guards had not opened fire on the two attackers, forcing them to detonate their explosives at least 50 yards from the office, police said. The bombing in Zumar, a town 45 miles west of Mosul, capital of Ninevah province, was the second suicide attack this week aimed at the party in that area. In other violence, four insurgents were killed as the U.S. targeted suspected al-Qaida in Iraq militants near Taji, a U.S. air base 12 miles north of Baghdad, the U.S. command said. It said two women and two children were also believed to have been killed during the fighting. "Unfortunately al-Qaida in Iraq continues to use women and children in their illegal activities," U.S. spokesman Christopher Garver said. Two civilians were killed and 12 wounded when mortar shells exploded in the southern Baghdad district of Dora, police said. One civilian died and four were wounded when a car bomb exploded in the Baiyaa district of southwestern Baghdad. At least 30 tortured bodies were found, including 27 who had been shot to death and left in different parts of Baghdad and three decapitated bodies found south of the capital. In Tikrit, police said the wife and daughter of a Saddam Hussein cousin were found slain at their home. The wife of Hashim Hassan al-Majid had been shot and the daughter strangled, police Capt. Samir Mohammed said. Their names were not released. Al-Majid's brother is Ali Hassan "Chemical Ali" al-Majid, one of the most notorious figures of Saddam's regime, who is on trial for his alleged role in gassing Kurds and other abuses during a crackdown on Kurds in the 1980s. Hashim Hassan Al-Majid, who held various posts in Saddam's government, was arrested after the regime fell, Tajik residents said.