WASHINGTON (CNN) -- Democratic lawmakers and staffers privately say they're closing in on a broad budget deal that would give President Bush as much as $70 billion in new war funding.

Congress is likely to pass an additional $70 billion in new war funds, Democrats tell CNN.

The deal would lack a key provision Democrats had attached to previous funding bills calling for most U.S. troops to come home from Iraq by the end of 2008, which would be a significant legislative victory for Bush.

Democrats admit such a move would be highly controversial within their own party. Coming just weeks after House Speaker Nancy Pelosi, D-California, vowed the White House would not get another dollar in war money this year, it would further antagonize the liberal base of the party, which has become frustrated with the congressional leadership's failure to push back on Bush's Iraq policy.

"The base will not be happy," said one senior Democratic aide, who requested anonymity to candidly discuss budget negotiations that have not been completed.

The Democratic aide acknowledged the president is likely to get new money for the wars in Iraq and Afghanistan before Congress adjourns for the year. "Yes, in the end, that's where we will be," the aide said.

A senior Republican aide also said both sides are nearing a deal that would give Bush a large chunk of the $200 billion in war funding he requested earlier this year. "We're not there yet, but we're close," the Republican aide said.

Privately, Democrats say they have little choice but to give the president at least some war funding because Senate Republicans have vowed to block any final budget deal unless it has at least some of the war funding Bush has requested.

The White House has also been aggressive about pointing out that Defense Secretary Robert Gates will have to start laying off some civilian employees and freezing some defense contracts unless the Pentagon gets new war money soon, putting vast political pressure on Democrats to give the troops more money before going home for Christmas.

"We're calling on Congress to fully fund the troops," White House press secretary Dana Perino said Wednesday. "The troops need the money. Secretary Gates has been very clear -- since November 14, he has said that there might have to be furlough notices that go out if we don't get the money."

Still, Democrats are trying to sell $70 billion in new war funding as a partial victory for them. They point out that while the final numbers are still in flux during intense private negotiations, Bush is likely to get far less money than he originally requested.

"What is for sure is he will not get all $200 billion," said one senior Democratic lawmaker. "Whatever number it is, it is much less than what the president asked for. For the first time in this war, he has received less than his request."

But senior administration officials privately say they expect to be able to get at least of the rest of the president's $200 billion request passed through Congress next year.

"They have not been able to change the president's policy," one senior official said flatly, expressing confidence the White House will continue to get more war funds as violence decreases in Iraq. E-mail to a friend

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