WASHINGTON — Rebuking President Bush on a war that enjoyed great support at its outset but has become deeply unpopular, the House went on record Friday opposing Bush's plan to add 21,500 troops in Iraq, with 17 Republicans joining all but two Democrats in voicing their disapproval.

Potentially adding to the power of the rebuke, the Senate plans to debate an identical measure today.

The House's nonbinding resolution — approved on a 246-182 vote, with Utah's lone Democrat, Jim Matheson, in the majority and two Republicans in the minority — was Congress' most forceful action yet to challenge Bush's conduct of the war after congressional elections. In November the Democrats were catapulted to a majority in both houses of Congress, largely by the public's growing frustration with the Iraq conflict.

Even some of the strongest opponents of the resolution voiced little faith Friday in Bush's escalation strategy, stressing instead the importance of backing the troops, supporting the commander-in-chief and showing steadfastness in fighting terrorism.

The White House and Republican House leadership had worked feverishly over four days of debate this week to stem defections from the GOP side, concerned about the political impact if a large majority of lawmakers opposed the president. Republican leaders also complained that Democrats did not allow them to offer alternative resolutions more supportive of the president.

But Democrats, confident that the public is with them on Iraq, argued that the war has been misguided and poorly executed and that sending the additional troops would only produce more American deaths without turning the tide of what has become a bitter civil war.

In a speech on the House floor earlier this week, Matheson said he opposed the troop surge because he wanted to see a new Iraq strategy that, ideally, adopted many of the recommendations from the Iraq Study Group report released late last year.

"Our troops have done everything we have asked of them. Their performance is a source of great admiration and pride for everyone in America," the Utah Democrat said in his speech. "At a minimum, we owe them a new approach and a thoughtful approach to the situation in Iraq and the pursuit of a comprehensive strategy for success."

Rep. Rob Bishop, R-Utah, who voted against the resolution and also spoke on the floor earlier this week, said the resolution was "deeply shallow" and purely political. Because it was non-binding, it would have no impact.