CBS News senior White House correspondent Bill Plante reports sources say Mr. Bush will call for a surge of troops to Iraq that may total 20,000 additional forces over time. The address is scheduled for 9 p.m. EST.
But the new Democratic-controlled Congress has other ideas — with many key members seeking a reduction in U.S. forces.
House Speaker Nancy Pelosi said newly empowered Democrats will not give President Bush a blank check to wage war in Iraq, hinting they could deny funding if he seeks additional troops.
"If the president chooses to escalate the war, in his budget request, we want to see a distinction between what is there to support the troops who are there now," she said in anon Face The Nation.
"The American people and the Congress support those troops. We will not abandon them. But if the president wants to add to this mission, he is going to have to justify it and this is new for him because up until now the Republican Congress has given him a blank check with no oversight, no standards, no conditions," said Pelosi, D-Calif.
The idea of sending more troops that is most controversial. A newindicates nearly 6 in 10 Americans either want troop levels lowered or a full withdrawal.
Some American troops on the ground in Iraq have said they need reinforcements to bring the sectarian violence plaguing the country under control.
But CBS News chief foreign correspondent Lara Logan reports the president's new initiative may disappoint them as well.
Logan says the kind of troop surge being discussed in Washington is a far cry from the "exponential" increase deemed necessary by the soldiers and commanders she has spoken to. She reflects that an infusion of U.S. forces last summer to the Iraqi capital actually had the exact opposite of its desired effect on the ground, leading to an increase in violence.
Logan says many in Iraq feel it is simply "too late" to try and make a peaceful country out of Iraq with the present government in place.
Regardless of how many U.S. troops are in Iraq, the key to quelling the violence is reigning in the sectarian militias that roam the streets and attack each other's civilian populations with impunity.
Many believe that senior Iraqi leaders — including Prime Minister Nouri al-Maliki — have strong ties to the militias, a situation that Logan points out would make it virtually impossible for his government to try and disarm the groups.
In Washington, when asked about the possibility of cutting off funding for the war, House Majority Leader Steny Hoyer declined to say whether Democrats might do so, saying only that the current strategy clearly is "not working."
"I don't want to anticipate that," said Hoyer, on "Fox News Sunday."
Republican Sen. Gordon Smith, who is critical of the surge, met with Mr. Bush on Monday and says the president understands what's at stake now, reports CBS News chief White House correspondent Jim Axelrod.
"I think the president understands the gravity of it. He understands he is betting his presidency, his place in history on this coming out well," Smith said.
Some military officials, familiar with the discussions, say Mr. Bush at first could send 8,000 to 10,000 new troops to Baghdad, and possibly Anbar Province, and leave himself the option of adding more later if security does not improve.