But Senate Democrats planned to hold votes on troop pullouts, hoping to capitalize on Republican defections to build a congressional majority around an exit strategy.

"A growing number of Republicans are now speaking against the failed strategy in Iraq, and that's good," said Senate Majority Leader Harry Reid.

"I think we will find the next couple of weeks, whether the Republicans who have said publicly they think the present course should change are willing to vote with us," the Nevada Democrat said.

At least one such Republican said she was willing to do so. Maine Sen. Olympia Snowe, an early critic of Bush's policy of adding troops to Iraq this year, told reporters she was ready to vote for binding legislation requiring a troop withdrawal.

The White House denied a New York Times report that debate was intensifying over whether Bush should try to prevent more Republican defections by announcing intentions for a gradual withdrawal of troops from high-casualty Iraqi areas.

"There is no debate right now on withdrawing forces right now from Iraq," spokesman Tony Snow said.

Following recent calls for a change in strategy by lawmakers such as Sen. Richard Lugar, the ranking Republican on the Senate Foreign Relations Committee, the Times said officials fear the last pillars of political support among U.S. Senate Republicans for Bush's Iraq policy were collapsing.

"POLITICAL JUDGMENT"

"The president has said many times, that as conditions required and merit, that there will be, in fact, withdrawals and also a pulling back from areas of Baghdad and so on," said Snow. "But the idea of trying to make a political judgment rather than a military judgment about how to have forces in the field is simply not true."

Reid said Senate debate on Iraq would be part of work on a defense policy bill. It would begin with a vote, possibly on Tuesday, on a plan by Virginia Democratic Sen. Jim Webb to establish minimum rest times between deployments for troops in Iraq, some of whom have done several tours of duty.

A vote would follow on a withdrawal plan by Michigan Democratic Sen. Carl Levin, the Armed Services Committee chairman. It is expected to require a reduction of U.S. troops to start soon with a goal of finishing the drawdown next spring.

Reid acknowledged he did not know whether he had the votes to overcome Senate procedural hurdles. While willing to work with Republicans unhappy with the war, he said he did not want to water down pullout proposals to a "fig leaf."

Snowe, a moderate Republican, told reporters she had not decided which proposal to support but had decided Congress needed to pass something requiring a troop drawdown. Waiting longer would "run the risk of losing another precious month with precious lives," she said.

Virginia Sen. John Warner, a leading Republican voice on defense who says Bush's Iraq strategy is drifting, recommended senators wait at least until the administration makes a July 15 report on Iraq required by a recent war funding bill.

"It seems to me we should hear the president out before we begin to ... make decisions," Warner said.

Conservatives like Sen. Thad Cochran of Mississippi speculated that few of his fellow Republicans would support troop withdrawal deadlines. "I'm supporting the president," said Cochran, the senior Republican on the committee overseeing war funding.