A politically weakened President George W. Bush implored a skeptical Congress to embrace his unpopular plan to send more US troops to Iraq, saying it represents the best chance in a war America must not lose. "Give it a chance to work," he said. Facing a political showdown with Democrats and Republicans alike, Bush was unyielding on Iraq in his annual State of the Union address Tuesday night. He also sought to revive his troubled presidency with proposals to expand health insurance coverage and to slash domestic gasoline consumption by 20 percent in a decade. Democrats and even some Republicans scoffed at his Iraq policy. Unmoved by Bush's appeal, Democrats said the House and Senate would vote on resolutions of disapproval of the troop buildup. "We need a new direction," said Sen. Jim Webb, picked by the Democrats to deliver their response to Bush. "The majority of the nation no longer supports the way this war is being fought; nor does the majority of our military," said Webb, a Vietnam veteran opposed to Bush's invasion of Iraq, in his prepared remarks. Republican Sen. Norm Coleman also took issue with Bush. "I can't tell you what the path to success is, but it's not what the president has put on the table," he said. Bush divided his speech between domestic and foreign issues, but the war was topic No. 1. With Congress poised to deliver a stinging rebuke on his troop increase, he made a personal plea to lawmakers. "I have spoken with many of you in person. I respect you and the arguments you made," Bush said. "We went into this largely united, in our assumptions and in our convictions. And whatever you voted for, you did not vote for failure." "Our country is pursuing a new strategy in Iraq, and I ask you to give it a chance to work," Bush said. "And I ask you to support our troops in the field and those on their way." Democratic Speaker Nancy Pelosi and Senate Majority Leader Harry Reid gave Bush a swift answer. "While the president continues to ignore the will of the country, Congress will not ignore this president's failed policy," they said in a joint statement after his address. "His plan will receive an up-or-down vote in both the House and Senate, and we will continue to hold him accountable for changing course in Iraq." Bush said the Iraq war had changed dramatically with the outbreak of sectarian warfare and reprisals. "This is not the fight we entered in Iraq, but it is the fight we are in," the president said. "Every one of us wishes that this war were over and won. Yet it would not be like us to leave our promises unkept, our friends abandoned and our own security at risk. "Ladies and gentlemen: On this day, at this hour, it is still within our power to shape the outcome of this battle," the president said. "So let us find our resolve and turn events toward victory." In his address, Bush reached out to Democrats, saying, "Congress has changed, but our responsibilities have not. We are not the first to come here with government divided and uncertainty in the air. Like many before us, we can work through our differences and achieve big things for the American people." Key Republicans have joined Democrats in drafting resolutions of opposition to the plans he announced two weeks ago to send an additional 21,500 troops to Iraq. Bush said his approach had the best chance to succeed, but clearly many lawmakers, and an overwhelming majority of Americans, disagree. "Many in this chamber understand that America must not fail in Iraq because you understand that the consequences of failure would be grievous and far reaching," the president said. "If American forces step back before Baghdad is secure, the Iraqi government would be overrun by extremists on all sides." In such a case, he forecast "an epic battle," Shi'ite extremists backed by Iran against Sunni extremists aided by al-Qaida and supporters of executed former President Saddam Hussein's government, leading to violence that could spread across the Middle East. "For America, this is a nightmare scenario," Bush said. Unlike the friendly Republican-dominated Senate and House of the past six years, the new Congress has not shied from challenging the president. "Our citizens don't care much which side of the aisle we sit on, as long as we are willing to cross that aisle when there is work to be done," said Bush, who for six years ignored Democrats' demands to be included in decisions. On immigration, the president made a plea to lawmakers that he has made before. Members of his own party were the main obstacle to success in that area, which Bush acknowledged even as he pressed for a better result now that Capitol Hill is run by Democrats more amenable to his ideas. "Convictions run deep in this Capitol when it comes to immigration," he said. "Let us have a serious, civil and conclusive debate." Bush said his proposals on energy would cut American imports by the equivalent of 75 percent of the oil coming from the Middle East. His prescription, as always, relied primarily on market incentives and technological advances, not government mandates. "America is on the verge of technological breakthroughs that will enable us to live our lives less dependent on oil," he said. "These technologies will help us become better stewards of the environment, and they will help us to confront the serious challenge of global climate change."