A long line of polls charted a steep decline in public approval for Republicans in the course of what Sen. John McCain, R-Ariz., pronounced a "shameful episode" in the nation's history.
While the emerging deal could well meet resistance from conservatives in the Republican-controlled House, the Democratic Leader, Rep. Nancy Pelosi of California, has signaled she will support the plan and her rank and file is expected to vote for it in overwhelming numbers.
That raised the possibility that more Democrats than Republicans would back it, potentially causing additional problems for House Speaker John Boehner as he struggles to manage his tea party-heavy majority.
Boehner and the House Republican leadership met in a different part of the Capitol to plan their next move. A spokesman, Michael Steel, said afterward that no decision had been made "about how or when a potential Senate agreement could be voted on in the House."
The developments came one day before the deadline Lew had set for Congress to raise the current $16.7 trillion debt limit. Without action by lawmakers, he said, Treasury could not be certain it had the ability to pay bills as they come due.
In addition to raising the debt limit, the proposal would give lawmakers a vote to disapprove the increase. Obama would have the right to veto their opposition, ensuring he would prevail.
House and Senate negotiators would be appointed to seek a deficit-reduction deal. At the last minute, Reid and McConnell jettisoned a plan to give federal agencies increased flexibility in coping with the effects of across-the-board cuts. Officials said that would be a topic for the negotiations expected to begin shortly.
Despite initial Republican demands for the defunding of the health care law often derided as "Obamacare," the pending agreement makes only one modest change in the program. It requires individuals and families seeking subsidies to purchase coverage to verify their incomes before qualifying.