As a timetable, it could hardly be clearer: Show progress in Iraq by July or begin withdrawing US troops. Meet your goals by October or start bringing the troops home. No matter what, all troops are out by August 2008.

By drawing their line in the sand, House Democratic leaders are trying to ratchet up pressure on the White House to change its Iraq strategy while trying to persuade Americans that there is another way forward on the war on terror. That direction, they say, involves intensifying the fight in Afghanistan while winding down involvement in Iraq.

As a practical matter, the legislation stands slim chance of passage as written. Antiwar House Democrats haven't yet signed on, and House Republican leaders condemned it. But as a gauge of America's war weariness, it may serve as a sounding board for a citizenry eager for solutions to a conflict that has proved frustratingly complex.

"We have to ... take the conversation to the American people and, hopefully, [President Bush] will hear them," House Speaker Nancy Pelosi said in announcing the plan Thursday on Capitol Hill.

After weeks of intense discussion within a deeply divided caucus, House Democratic leaders released their multifaceted funding plan. It adds $4 billion to Mr. Bush's $95.5 billion request for the Defense Department, including significant increases for military readiness and healthcare and housing for returning troops.

It also requires the president to certify that "benchmarks of accountability" for the Iraqi government are met and that US forces are not sent into combat without meeting the military's own basic guidelines for unit readiness, including a year at home before redeployment to Iraq.

The plan sets two key dates for the president to certify "meaningful and substantial progress" in meeting political and military benchmarks: July 1 and Oct. 1, 2007. If the president cannot meet that requirement, the plan calls for the immediate redeployment of US forces out of Iraq, to be completed within 180 days.

"Unless there is progress made in meeting benchmarks by July 2007, we begin the redeployment of our troops out of a combat role in Iraq," said Speaker Pelosi.

If they are met, the Secretary of Defense must begin redeploying US forces out of Iraq by March 1, 2008, and complete the redeployment within 180 days, she added.

The deal aims to strike a balance between two often competing wings of the House Democratic caucus: conservatives, who oppose any move to "micromanage" the war, and the liberal "Out of Iraq" caucus, which wants to see the newly empowered Democrats use war funding to leverage an end to the war now.

The 44-member Blue Dog Coalition, which opposes any move that threatens to deprive US troops of funding, and other center-right Democrats have been urging leaders to give the president a waiver in any plan that tried to impose conditions on the spending of war funds. Pelosi confirmed that such waivers would be part of the plan but did not specify how they would affect the timetable for withdrawal.

Even before full details of the Democratic proposal were released, leaders of the more liberal 71-member Progressive Congressional Caucus urged caution in supporting it. "There are many people talking about voting against this bill," said Rep. Lynn Woolsey (D) of California, who chairs the caucus. She and others at a press briefing on Thursday say they are calling for a vote on an amendment by Rep. Barbara Lee (D) of California that requires completion of the withdrawal not later than Dec. 31, 2007. "The American people expect Democrats to end this war now," said another caucus member, Rep. Dennis Kucinich (D) of Ohio.

House Republican leader John Boehner attacked the measure. He said the legislation amounted to "establishing and telegraphing to our enemy a timetable" that would result in failure of the US mission in Iraq.

To pass the House, the legislation needs 218 votes. "We are a caucus, and we will come together and find our common ground," Pelosi said. She also said that she didn't know what purpose it would serve to allow a vote on the Lee amendment.

At press time, most lawmakers were still learning details of the agreement and not ready to commit either way on a vote.

To boost prospects for a positive vote, Democrats have packed the bill – officially, the US Troop Readiness, Veterans' Health and Iraq Accountability Act – with new funding for issues ranging from hurricane recovery on the Gulf Coast to veterans' health.

These include $1.7 billion to enhance medical services for active duty forces and mobilized reserves, and their family members – an especially high-profile issue in Washington after recent press reports of poor treatment at the Walter Reed Army Medical Center in Washington, D.C. [Editor's note: The original version incorrectly named and located Walter Reed Army Medical Center.]

Democrats also propose adding $1.4 billion to cover the full cost of housing allowances for military members in this fiscal year, $2.5 billion to address training and equipment shortfalls in forces not deployed to theaters of operation, $1.4 billion to purchase highly touted mine-resistant vehicles – an increase of $311 million above the president's request.

The plan also recommends reductions to several high-profile programs requested by the president, including denial of funding for two Joint Strike Fighter purchases and five of the six EA-18G electronic attack airplanes requested by the Navy.