Majority Leader Harry Reid, D-Nev., and GOP leader Mitch McConnell of Kentucky could seal an agreement today, just two days before the Treasury Department says it will run out of borrowing capacity.
The emerging pact would reopen the government through Jan. 15 and permit the Treasury to borrow normally until early to mid-February, easing dual crises that have sapped confidence in the economy and taken a sledgehammer to the GOP's poll numbers.
"The general framework is there" between Reid and McConnell, said Sen. Bob Corker, R-Tenn. He said conversations with the House were continuing and he thought it would be midday at the earliest before a plan was finalized.
President Barack Obama telephoned McConnell on Monday to talk about the emerging deal, a McConnell aide said. Congressional leaders had been scheduled to meet with Obama at the White House on Monday, but the meeting was postponed to allow more time for negotiations.
On Wall Street, futures were mixed early Tuesday, with investors somewhat optimistic over a potential deal.
Sen. Mark Pryor, an Arkansas Democrat who was part of the bipartisan group known as the Gang of 12 which labored over the weekend to end the stalemate, said Tuesday he was "pretty confident" the Senate leadership and the White House would announce an agreement some time later in the day.
Speaking of the House, Pryor told CNN that "some Republicans are, quite honestly, they're acting childish about this. They almost want a shutdown. They almost want to see us break the debt ceiling."
Sen. Amy Klobuchar, D-Minn., also a part of the Gang of 12, told "CBS This Morning" she believes an agreement is near that "doesn't contain a lot of the partisan pills" that sank earlier proposals. She said it's urgent that national leaders find solutions to vexing issues so that the country doesn't "lurch from one financial crisis to another."
Many House conservatives were unhappy about the emerging framework, though it remained to be seen whether they would seek to change it.
"One of the things we want to test is just basic fairness," Rep. Steve Scalise of Louisiana, chairman of the Republican Study Committee, an influential group of House conservatives, said on CNN Tuesday. He was asked how conservatives would respond to the plan taking shape in the Senate. "One of the things we don't want to see is just another patch," he said.
"We're willing to get the government open. We want to get the government open," Scalise said. "Hopefully they get something done that addresses the spending issue."
The developing plan is a far cry from the assault on "Obamacare" that tea party Republicans originally demanded as a condition for a short-term funding bill to keep the government fully operational. It lacks the budget cuts demanded by Republicans in exchange for increasing the government's $16.7 trillion borrowing cap.
Nor does the framework contain any of a secondary set of House GOP demands, like a one-year delay in the health law's mandate that individuals buy insurance. Instead, it appeared likely to tighten income verification requirements for individuals who qualify for Obamacare subsidies and may repeal a $63 fee that companies must pay for each person they cover under the big health care overhaul beginning in 2014.
Democratic and Republican aides described the outlines of the potential agreement on condition of anonymity because the discussions were ongoing.
But with GOP poll numbers plummeting and the country growing weary of a shutdown entering its third week, Senate Republicans in particular were eager to end the shutdown -- and avoid an even greater crisis if the government were to default later this month.
Any legislation backed by both Reid and McConnell can be expected to sail through the Senate, though any individual senators could delay it.
But it's another story in the House, where it wasn't winning a lot of fans among conservatives.