One likely result of the report will be a vastly accelerated debate among President Bush's top aides on withdrawing troops and scaling back the U.S. presence in Iraq.
A senior Pentagon official tells CBS News chief White House correspondent Jim Axelrod ato determine what conditions must exist, short of victory, to begin pulling troops out of Iraq.
The "pivot point" for addressing the matter will no longer be Sept. 15, as initially envisioned, when a full report on Bush's so-called "surge" plan is due, but instead will come this week when the interim mid-July assessment is released, the official said.
A draft version of the report, expected to be presented to Congress on Thursday or Friday, circulated among various government agencies in Washington on Monday.
"The facts are not in question," the official told The Associated Press, speaking on condition of anonymity. "The real question is how the White House proceeds with a post-surge strategy in light of the report."
The official said it is highly unlikely that Bush will withhold or suspend some aid to the Iraqis based on the report, as he can do under the law.
As the White House prepared its first major progress report for Congress, war-weary Republicans are focusing their efforts on protecting unrelated anti-terrorism programs while Democrats are trying again to pass legislation ordering troop withdrawals.
Simmering in the background is a growing sentiment among at least some Republicans that the U.S. strategy is failing and Bush should adopt a new policy before they must face their constituents during the August recess.
Clearly political support is weakening inside the administration, adds Axelrod. A senior administration official who has been to Iraq many times tells CBS News the Iraqis have made the surge "a joke," adding that they lack the ability, the firepower and the discipline to take over anything.
The Senate began debate Monday on legislation that would authorize $649 billion in defense programs. By week's end, senators are expected to vote on an amendment by Sen. Carl Levin, D-Mich., that would order troop withdrawals to begin in four months, with the goal of completing the pullout by spring 2008.