"We cannot cut and run," the battle plan says at one point, anticipating Democratic calls for a troop withdrawal on a fixed timetable.

As debate got under way in the House on Thursday, the Senate sent the president an additional $66 billion for military operations in Iraq and Afghanistan - legislation Bush promptly signed - and the Pentagon announced the U.S. death toll for the war had reached 2,500.

"It's a number," White House press secretary Tony Snow said of the grim milestone. He said Bush "feels very deeply the pain that the families feel."

The president has tried to rally support for the Iraq war in the days since the death of terror leader Abu Musab al-Zarqawi and the recent completion of a new Iraqi government.

But as the death toll and price tag of the conflict continue to rise, opinion polls show voters increasingly frustrated with the war and favoring Democrats to control Congress instead of the Republicans who now run the show.

Sensitive to those political realities, Republicans in both the Senate and House sought to put lawmakers of both parties on record on an issue certain to be central in this fall's congressional elections.

In the House, Republicans defended the Iraq war as a key part of the global fight against terrorism while Democrats called for a new direction in the conflict.

Partisan politics took center stage. Republicans painted Democrats as quitters who advocate a cut-and-run strategy and Democrats derided Republicans as Bush foot soldiers who refuse to challenge him.

"Many, not all, on the other side of the aisle lack the will to win," Rep. Charles Norwood R-Ga., said.

In turn, Rep. Rahm EmanuelD-Ill., asserted: "The Republican Congress sat and watched the administration make mistake after mistake after mistake."

Rep. Phil Gingrey R-Ga., stuck to the GOP script, saying, "In this fight for the future of peace, freedom and democracy in the Middle East and around the globe, winning should be our only option."

"Stay and we'll pay," argued Rep. John Murtha D-Pa., who criticized "the failed policy of this administration" and lamented the lives lost, billions of dollars spent and the bruised U.S. image since the war started.

On the other side of the Capitol, the Senate vote unfolded unexpectedly as the second-ranking GOP leader, Sen. Mitch McConnell, R-Ky., introduced legislation he said was taken from a proposal by Sen. John Kerry, the Massachusetts Democrat and war critic. It called for Bush to agree with the Iraqi government on a schedule for withdrawal of combat troops by Dec. 31, 2006.

Democratic leader Harry Reid sought to curtail floor debate on the proposal, and the vote occurred quickly. Six Democrats, including Kerry, were in the minority.

Senate Majority Leader Bill Frist, R-Tenn., predicted that terrorism would spread around the world, and eventually reach the United States if the United States were to "cut and run" before Iraq can defend itself.

But Reid, D-Nev., countered: "Two things that don't exist in Iraq and have not, weapons of mass destruction, and cutting and running.