Washington ? The Democratic-controlled House voted Thursday night to pay for military operations in Iraq on an installment plan, defying President Bush’s threat of a second straight veto in a fierce test of wills over the unpopular war.

The 221-205 vote was largely along party lines and sent the measure to a cool reception in the Senate, where Majority Leader Harry Reid, D-Nev., is seeking a compromise with the White House and Republicans.

Under growing political pressure from Republicans, Bush coupled his veto threat with a sign of flexibility. Visiting the Pentagon, he said he was willing to sign a military money bill that includes political and military goals for the Iraqi government.

“Time’s running out, because the longer we wait the more strain we’re going to put on the military,” said the president, who previously had insisted on what he termed a “clean” war funding bill.

Bush and key lawmakers have expressed increased frustration with the government in Baghdad in recent weeks, and Iraqi Deputy Prime Minister Barham Saleh spent his day appealing to key senators for patience.

Bush vetoed an Iraq funding bill last week, objecting to a timetable for troop withdrawal that was included as well as several billion dollars for domestic programs. After failing to override the veto, Democrats began work on a replacement measure, hoping to clear a bill the president will sign within two weeks so the flow of money to the troops is not interrupted.

That will inevitably require the party’s rank and file to make additional concessions. The withdrawal timetable already has been jettisoned. But for the time being, Speaker Nancy Pelosi of California has decided to defy Bush before negotiating with him.

“Democrats are not going to give the president a blank check for a war without end,” she said, advancing two bills for votes during the day that challenged the commander in chief’s conduct of the war.

The first would have required the withdrawal of U.S. combat forces from Iraq within nine months. It fell, 255-171, with most Republicans in opposition along with 59 Democrats.

Republicans argued that a withdrawal would be disastrous.

“Now is not the time to signal retreat and surrender. How could this Congress walk away from our men and women in uniform,” said Rep. Jerry Lewis, R-Calif.