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Senate negotiations over a possible debt-ceiling compromise have triggered immediate concerns about whether a majority of lawmakers in the House could be convinced to go along with it.

The partisan divide in the House is arguably wider than it is in the Senate. As details emerged Sunday of a tentative bipartisan Senate agreement, sources suggested those drafting it will face a tough sell in the other chamber -- with both parties.

One Senate Democratic aide predicted the president's base will "go bonkers" when the specific contents of the compromise legislation are disclosed.

Rep. Raul Grijalva, D-Ariz., co-chairman of the House Progressive Caucus, issued a searing statement Sunday calling the latest framework "a cure as bad as the disease."

"This deal trades peoples' livelihoods for the votes of a few unappeasable right-wing radicals, and I will not support it," Grijalva said, citing concern that it would cut entitlement benefits.

But several sources predicted particular trouble ahead within the House Republican caucus over issues ranging from defense cuts to a balanced-budget amendment -- presuming a package can clear the Senate first.

For starters, the emerging deal is modeled in part after the plan House Speaker John Boehner put forward before objections from Tea Party conservatives forced its revision. The fact that Senate negotiators are now returning to the Boehner framework, while inserting a handful of changes that could work to Democrats' advantage, may not sit well with those Tea Party-aligned freshmen.

"Tea Party won't be happy," one Republican lawmaker who supports the plan told Fox News, adding that "they never will be."

Boehner was preparing to brief the rank-and-file on the plan at some point, as rumors flew about what a compromise would look like.

"Those talks are moving in the right direction, but serious issues remain. And no agreement will be final until Members have a chance to weigh in," the speaker said in an email to members obtained by Fox News.

Lawmakers have only until Aug. 2 to reach a deal -- after that date, the Obama administration says the Treasury will no longer be able to pay all its bills.

A few components of the emerging deal stand out as potential roadblocks in the conservative wing.

Unlike the House-passed bill, the framework of this plan would not require Congress to pass a balanced-budget amendment in order to raise the debt cap. Though it would call for a vote on such an amendment, some conservatives want the balanced-budget amendment component to have more teeth.

"We need a balanced-budget amendment sent to the states," Rep. Tom Graves, R-Ga., told Fox News. "This is the time. If we're going to get it done, we've got to do it now."

Graves voted against the earlier House proposal and said he would probably oppose the emerging plan as well.

The plan would also be designed to lift the debt ceiling through early 2013. Though the vote could be split into two phases, the framework of the plan would make it very difficult to stop those increases. Under the rough outline, Congress would need to corral a two-thirds majority vote to block President Obama from winning the increase -- this is a change from the earlier Republican plan which tied a second debt-ceiling hike early next year to a new round of spending cuts.

Finally, concerns were mounting about what might happen during the second phase of deficit reduction prescribed by the plan. Under the framework, the first phase would immediately cut about $900 billion, sources said, but a special committee would be tasked with finding at least another $1.5 trillion in savings. The tricky part is finding a way to compel lawmakers on both sides of the aisle to follow through with the committee's recommendations. To do this, lawmakers are considering a provision that would "trigger" $1.2 trillion in across-the-board cuts, with an emphasis on defense cuts, if the recommendations are not approved.

One Republican official said the threat of military cuts could be a "key problem." Another source said dozens of Republicans on the House Armed Services Committee could reject such a plan.

Given the circumstances, the GOP lawmaker said the House will "need some (Democratic) votes" to get such a package over the finish line. The lawmaker indicated that if the president endorses the plan, Democrats will follow.

Moving forward, the president may be called upon to help do the heavy lifting in bringing other House Democrats on board.

That scenario could put Boehner in a difficult position within his caucus. But House Republican Whip Kevin McCarthy, R-Calif., dismissed the suggestion that a push to find bipartisan support could jeopardize Boehner's status. He told "Fox News Sunday" that Boehner has been a "leader" throughout the debt-ceiling process.