House Speaker John Boehner, R-Ohio, walks away from the microphone during a news conference after a House GOP meeting on Capitol Hill, Tuesday, Oct. 15, 2013, in Washington. House GOP leaders Tuesday floated a plan to fellow Republicans to counter an emerging Senate deal to reopen the government and forestall an economy-rattling default on U.S. obligations. But the plan got mixed reviews from the rank and file, and it was not clear whether it could pass the chamber. (AP Photo/ Evan Vucci)

WASHINGTON (AP) -- Their backs against the wall, House GOP leaders scrambled Tuesday to forge a plan to counter an emerging bipartisan Senate deal to reopen the government and forestall a default on U.S. obligations.

But the effort fell into disarray amid grumbling by party conservatives and it was unclear whether GOP leaders could keep it afloat — even as the potential peril to the U.S. economy deepened with a debt deadline less than two days away.

Though Republicans appeared to back off earlier demands for spending cuts as a condition of raising the government's borrowing cap, the partisan standoff between Democrats and House Republicans continued with little certainty over how Congress would bring about the end to the crises.

Jittery investors sent stocks modestly lower.

It was not clear whether the House GOP plan could pass the chamber.

The House measure mirrors in several respects a Senate plan that has generally taken shape. The House would suspend a new tax on medical devices for two years and take away the federal government's health care contributions to lawmakers and top administration officials. It would also fund the government through Jan. 15 and give Treasury the ability to borrow normally through Feb. 7, provisions embraced by Senate leaders in both parties.

House Speaker John Boehner, R-Ohio, said he's "trying to find a path forward" but that "there have been no decisions about exactly what we will do." He told a news conference, "There are a lot of opinions about what direction to go." GOP leaders went behind closed doors to massage the plan in hopes of a vote later Tuesday.

Senate Majority Leader Harry Reid, D-Nev., involved in negotiations with Senate GOP Leader Mitch McConnell of Kentucky, blasted the House plan as a blatant attack on bipartisanship. Senate talks appeared on hold as Boehner weighed his next move.

"It can't pass the Senate and it won't pass the Senate," Reid said. That sparked an angry response from Sen. John McCain, R-Ariz., who accused Reid of "piling on" and urged him to consider the House effort as a good-faith offer.

"We know you have the upper hand," McCain said. "Isn't it time that we find a way out of this?"

House Democratic leader Nancy Pelosi, D-Calif., said it was clear that Boehner "did not have the votes" for the House leadership plan. Pelosi said the Reid-McConnell plan has "struck fear in the hearts of the House Republicans," who she said want to "sabotage the bipartisan effort" in the Senate.

The developments came as a partial shutdown entered its third week and less than two days before the Treasury Department says it will be unable to borrow and will rely on a cash cushion to pay the country's bills.

The House GOP plan wouldn't win nearly as many concessions from President Barack Obama as Republicans had sought but it would set up another battle with the White House early next year.

Rep. Walter Jones, R-N.C., said he was not sure he could vote for the plan because it did not address the debt. "I have to know a lot more than I know now," he said.

The House move comes after conservative lawmakers rebelled at the outlines of an emerging Senate plan by Reid and GOP leader McConnell. Those two hoped to seal an agreement on Tuesday, just two days before the Treasury Department says it will run out of borrowing capacity.

Obama planned to meet with House Democratic leaders Tuesday afternoon as negotiations continue.

"The latest proposal from House Republicans does just that in a partisan attempt to appease a small group of tea party Republicans who forced the government shutdown in the first place," said White House spokeswoman Amy Brundage. "Democrats and Republicans in the Senate have been working in a bipartisan, good-faith effort .... With only a couple days remaining until the United States exhausts its borrowing authority, it's time for the House to do the same."

Political pressure is building on Republicans to reopen the government and GOP leaders are clearly fearful of failing to act to avert a default on U.S. obligations.

Republicans are in a difficult spot, relinquishing many of their core demands as they take a beating in the polls. As the Republicans met privately to discuss the latest plan, Rep. Steve Southerland, R-Fla., led them in several verses of "Amazing Grace."

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