Privately, Members on both sides of the aisle are questioning Bush's decision to push for the cuts, particularly as the administration is already being criticized for problems with the recent rollout of the Medicare prescription drug program.

"I can't imagine that the majority party here ... will let this come through in an election year," said Sen. Tom Harkin (D-Iowa) during a press conference in which he pounced on the president's proposed health care cuts as "heartless."

Indeed, that is exactly the kind of criticism Republicans quietly fear from Democrats this year as Republicans' favorability ratings have been sinking along with the president's.

"It strikes me that [the White House] isn't thinking about the election at all," said one senior Senate Republican staffer. "I can't quite figure out why they are going to make us jump off this cliff."

And it appears that few are looking forward to a repeat of last year's bruising intraparty battles between conservatives and moderates over cuts to entitlement spending.

"Probably we would prefer not to have it this year, but it happens every year, so we're just used to it," said Sarah Chamberlain Resnick, executive director of the Republican Main Street Partnership, many of whose members face tough re-election races in Democratic-leaning districts.

Bush's fiscal 2007 budget proposes slowing Medicare's growth rate by nearly $36 billion over five years by reducing government payments for hospitals, skilled nursing facilities and home health care. Additionally, higher-income seniors would have to pay increased Medicare premiums.

"Seniors are already angry about the drug benefit, and now they're saying we should increase premiums for [seniors with] higher incomes?" the senior Senate Republican aide asked incredulously.

Bush also called this year for nearly $5 billion in cuts to Medicaid, the government health insurance program for the poor and disabled.

Despite some nervousness about reigniting the spending debate, particularly among those up for re-election, there is still a core faction of conservatives in both chambers pushing for another budget that calls for cuts to entitlements, such as Medicare and Medicaid.

"Under the president's budget, we would increase spending for Medicare by 7.5 percent every year for the next five years, rather than by 7.8 percent. That is not a 'cut,'" Rep. John Shadegg (R-Ariz.), a leading fiscal conservative, said in a statement. "The program will still spend more than $2 trillion in those years. Surely at a time of war, and facing a mountain of debt, it is reasonable to slow the growth of spending by three-tenths of 1 percent."

Similarly, Senate Budget Chairman Judd Gregg (R-N.H.) said Congress needs to continue the success it had in cutting entitlements last year and that he would use the president's proposed cuts to Medicare and Medicaid as the basis for any budget reconciliation measure this year.

Still, Gregg bemoaned "the usual grandstanding that comes in this area" and said those complaining about having the debate again have "absolutely no political courage."

"You cannot demagogue this issue any longer," Gregg added.

Still, lawmakers in both parties immediately pushed back at the administration on Monday when the proposed entitlement cuts were revealed.

Resnick said the president is unlikely to get all he's asking for on entitlement cuts anyway.

"This is only the beginning. This will end up being compromised out," she said. "This will once again force the [GOP] moderates to hang together and forge a compromise."

That's exactly what happened during last year's budget debate, when Bush asked for a $60 billion cut in Medicaid's growth over 10 years, primarily from targeting fraud and abuse. GOP centrists, concerned that poor beneficiaries would suffer from any cuts, pared that down to just $7 billion in savings. An additional $6.4 billion was trimmed from Medicare.

But it's not just centrist Republicans who are reacting coolly to the proposed cuts in Bush's budget. Conservatives such as Sen. Rick Santorum (R-Pa.), who has been trailing his Democratic challenger in polling since last year, are also signaling their displeasure.

"The Senator appreciates the president putting forth a budget that restrains spending, but he is also going to take a long, hard look at issues important to Pennsylvania," said Santorum spokesman Robert Traynham. He added that Santorum is particularly concerned about the president's proposed cuts to Medicare, Community Development Block Grants and Social Services Block Grants.

"If you look at [the president's] popularity right now - and the popularity in general of Republicans and the popularity of Congress overall - this is not something that you want to go head-over-heels and support unless you are in a nice, cozy 75 percent-for-re-election Republican district," said one Republican source.

Still, others said that the GOP's commitment to fiscal responsibility would end up as a boon come Election Day in November.

"In 2002 and 2004, we saw Democrats use very similar tactics, whether it was scaring old people or painting Republicans as anti-child," said Brian Nick, spokesman for the National Republican Senatorial Committee. "Cuts to entitlement programs are not something I think will hurt Republicans in '06."

Democrats disagree. "The president is going to have a very tough sell up here," said one Senate Democratic aide of the entitlement cuts. "He does play a little into our hand on this. I don't know what he's thinking."