The difference is due in part to the fact that the Reid plan would extend the debt ceiling for a longer period of time than would the Boehner plan, which would call for a two-step process.

Still, the news could deal a further blow to Boehner’s proposal, which is slated to come up for a vote in the House on Thursday. The report comes as House Republicans have postponed a vote on the Boehner measure after the CBO said Tuesday evening that Boehner’s plan results in only $850 billion deficit savings, not the $1.2 trillion projected by GOP leaders when the plan was unveiled Monday.

“In total, if appropriations in the next 10 years are equal to the caps on discretionary spending and the maximum amount of funding is provided for the program integrity initiatives, CBO estimates that the legislation would reduce budget deficits by about $2.2 trillion between 2012 and 2021 relative to CBO’s March 2011 baseline adjusted for subsequent appropriation action,” the budget office said in its analysis of the Reid proposal.

The $2.2 trillion in deficit savings projected by the CBO is less than the $2.7 trillion that Senate Democratic leaders had originally said the plan would achieve. The report could also mean that Reid, like Boehner, might have to re-work his plan in order to achieve his target number.

Michael Steel, a Boehner spokesman, said in a statement Wednesday that the report “shows the Senate plan for what it is: a grab-bag of gimmicks that gives the president a blank check.”

“In contrast to the bill House Republicans have offered, the Senate Democratic bill counts as ‘savings’ a trillion dollars in war money that would never have been spent - and on top of that, slashes the defense budget in a manner that would hurt our men and women in uniform in a time of war,” Steel said.

“It relies on smoke and mirrors for half of its ‘savings,’ yet still cuts $500 billion less than promised.”

Rallying behind the Boehner plan Wednesday morning was Senate Minority Leader Mitch McConnell (R-Ky.), who said in remarks on the Senate floor that the proposal reflects the spending cuts preferred by President Obama.

“From what I can tell, the only thing in this bill the resident hasn’t already expressed his support for either publicly or privately is that it doesn’t get him through his election without having to engage in another national discussion about the debt crisis that’s brought us to this point,” McConnell said. “So I would ask these senior advisors whether that’s a position they want to put the president in. Do they really intend to suggest that he veto the nation into default for political reasons?”

House Republicans were holding a morning conference meeting at a basement room in the Capitol to further discuss the way forward as the Aug. 2 deadline for raising the country’s debt ceiling looms six days away.

Rep. Mike Rogers (R-Mich.), the chairman of the House Intelligence Committee and a Boehner ally, said that leaders will “re-work” the plan and that Tuesday’s news from the CBO “isn’t a big deal.”

Even so, several rank-and-file members who had already said they were undecided about the Boehner proposal said Wednesday morning that they remained so – with several saying that Tuesday’s CBO report had made them less likely to support the plan.

“What in the CBO report would make me want to support the plan?” asked freshman Rep. Steve Southerland (R-Fla.), who is officially undecided on the proposal. Southerland said that while leaders were working on achieving deeper cuts, the framework still does not address the issue of whether the deficit savings are enough to avoid a downgrade by the leading credit rating agencies.

“”It doesn’t remedy the issue of a downgrade, and that’s of terrible concern to me,” he said.

Rep. Raul Labrador (R-Idaho) said he, too, was not sure whether he would back the Boehner plan.

“I’m not sure yet; I’m just looking at the plan,” said Labrador, a freshman who is also among the 39 House Republicans signing the “cut, cap and balance” pledge to oppose any debt-ceiling increase that doesn’t include congressional passage of a balanced budget amendment. “There are certain aspects of it I don’t like. That’s why I’m coming to every meeting I can to make sure that I get as much information as possible.”

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