WASHINGTON – A day before Bush was to deliver a major address on the war, Senate Democrats rejected a four-star general’s recommendation to keep some 130,000 troops in Iraq through next summer and called for legislation that would sharply limit the mission of American forces.

Their proposal was not expected to set a deadline to end the war, as many Democrats want, but instead restrict troops to a narrow set of objectives: training the Iraqi military and police, protecting American assets, and fighting terrorists, party officials said.

The goal of the tempered measure is to attract enough Republican votes to break the 60-vote threshold in the Senate needed to end a filibuster — something Democrats have been unable to do since taking control of Congress eight months ago.

“I call on the Senate Republicans to not walk lockstep as they have with the president for years in this war,” Senate Majority Leader Reid, Democrat of Nevada, said at a Capitol Hill news conference. “It’s time to change. It’s the president’s war. At this point it also appears clear it’s also the Senate Republicans’ war.”

The developments today reflected a struggle by Democrats to regain momentum in the war debate, dominated by two days of testimony by the top commander in Iraq, General David Petraeus, and the American ambassador there, Ryan Crocker.

General Petraeus said the 30,000 troop buildup initiated earlier this year had yielded some security gains and needed more time. He recommended slowly reversing the buildup, drawing down about 5,500 soldiers and Marines by the end of the year and returning to 130,000 troops next summer.

Mr. Reid and other Democrats swiftly rejected the proposal, saying it does not go far enough.

“It creates and provides an illusion of change in an effort to take the wind out of the sails of those of us who want to truly change course in Iraq,” Senator Levin, Democrat of Michigan, said.

In a bold challenge to General Petraeus’s assessment of Iraq, Mr. Reid said the “situation on the ground in Iraq has not changed at all.” He later conceded some gains had been made in the western Anbar province, “but it’s like the big balloon that you push on one side and it comes out someplace else.”

Whereas General Petraeus’s assessment inflamed Democrats, it assuaged many Republicans. And while it prompted tough questions from several Republican skeptics, including Senators Warner of Virginia and Collins of Maine, most said they were still reluctant to impose a firm timetable on the war.

Senator Coleman, Republican of Minnesota, seen as another potential swing vote on the war, said he was working with Senator Pryor, Democrat of Arkansas, on legislation that would put General Petraeus’s recommendations into law.

Absent a new political climate, Democrats are in a tough position: continue to insist on a hardline position and fail, letting weeks go by without passing anti-war legislation, or soften their stance.

Mr. Reid and other leading Senate Democrats huddled in Mr. Reid’s office today to discuss their next steps. At issue was how far to go in forcing a new mission for troops without losing support from either side of the political spectrum, according to congressional aides familiar with the meeting.

If the legislation is nonbinding and only urges Mr. Bush to refocus the mission, the bill could lose support from more liberal Democrats such as Senators Feingold, Democrat of Wisconsin, Senator Kerry, Democrat of Massachusetts, and Senator Boxer, Democrat of California, who don’t want a watered-down debate. On the contrary, if the bill orders the mission change by a certain date, it might turn off moderates like Mr. Warner and Ms. Collins.

Mr. Reid declined to discuss details of the plan today, saying only that Democrats would offer four to six amendments “to change the course of the war” when the Senate takes up a defense bill next week. Among those will likely be legislation by Senator Webb, Republican of Virginia, that would require troops spend as much time home as they do in combat.

Among the Republicans working with Messrs. Reid and Levin on anti-war legislation include Senator Hagel, Republican of Nebraska, and Senator Smith, Republican of Nebraska, two GOP senators who long ago turned against the war.

In a 15-minute address from the White House at 9 p.m. tomorrow, Mr. Bush will endorse General Petraeus’s recommendations, administration officials said. The White House also plans to issue a written status report on the troop buildup on Friday, they said. The officials spoke on condition of anonymity because Mr. Bush’s speech is not yet final.

While mirroring General Petraeus’s strategy, Mr. Bush will place more conditions on reductions than his general did, insisting that conditions on the ground must warrant cuts and that now-unforeseen events could change the plan.

Earlier today, Secretary of State Rice said that stabilizing Iraq meant more than improving security within its borders and included “the territorial security of Iraq” with respect to its Mideast neighbors, especially Iran.

“Iran is a very troublesome neighbor,” she said on NBC’s “Today” show. “Iran is prepared to fill the vacuum” if America leaves Iraq.

In a joint press conference with Mr. Crocker today, General Petraeus said Iranians appear to be trying to create a like Hezbollah-like organization in Iraq that they could use to gain influence inside the fractured country.

On Friday, the president will travel to a Marine base in Quantico, Va., just outside Washington, to talk further about his Iraq policy, the White House announced. Vice President Cheney will do his part, too, speaking on Iraq on Friday at appearances at the Gerald R. Ford Presidential Museum in Grand Rapids, Mich., and at MacDill Air Force Base in Florida.