WASHINGTON – The Senate is on the verge of a bipartisan agreement to reopen the federal government and stave off potential default but major hurdles remain – most particularly the House of Representatives.

Senate Democratic Leader Harry Reid, of Nevada, and Senate Republican Leader Mitch McConnell, of Kentucky, worked through most of Monday to arrive at a package both sides could live with. Concurrence on a blueprint is said to be near. And congressional staff still has to develop legislative language that passes muster.

According to several lawmakers close to the ongoing negotiations, the Senate will be asked to raise the nation’s debt ceiling to Feb. 7 and adopt a temporary spending bill to fund the federal government through Jan. 15. As part of the deal, the two factions will attempt to bang out a full spending and tax plan.

The agreement will also make a few minor changes to the Affordable Care Act, popularly known as Obamacare, the heart of the budget dispute that led to a partial governmental shutdown now in its second week. A provision sought by Republicans would establish stronger regulations to assure that those seeking subsidies to buy health insurance, as required by the law, are qualified. In exchange for meeting that Republican condition, Democrats are seeking a delay until 2015 of a tax on health insurance policies that is expected to add about $63 per individual to the cost beginning in January.

Reid recessed the Senate for the day Monday evening, meaning no action will be taken on any deal until Tuesday at the earliest. Time is of the essence since the Treasury Department’s authorization to borrow money to fund the federal government is expected to run dry Oct. 17 when it bumps up against the $16.7 trillion debt ceiling. President Obama warned again Monday that congressional failure to raise the debt ceiling would leave the government without the money necessary to pay its bills.

“This week, if we don’t start making some real progress, both the House and the Senate, and if Republicans aren’t willing to set aside their partisan concerns in order to do what’s right for the country, we stand a good chance of defaulting, and defaulting could have a potentially devastating effect on the economy,” Obama said while dealing out sandwiches at Martha’s Table, a Washington food bank.

Both Reid and McConnell expressed optimism during the day that some agreement could be reached.

“We have had an opportunity over the last couple of days to have some very constructive exchanges of views about how to move forward,” McConnell said. “Those discussions continue and I share [the] optimism that we’re going to get a result that will be acceptable to both sides.”

Talks were progressing so smoothly that an afternoon meeting involving the president, Reid, McConnell, House Speaker John Boehner (R-Ohio) and House Democratic Leader Nancy Pelosi, of California, was postponed so the parties could continue to work things out.

“We’ve made tremendous progress,” Reid said. “We are not there yet, but tremendous progress. And everyone just needs to be patient. Perhaps tomorrow will be a bright day.”

One major sticking point was the length of the temporary spending measure, known as a continuing resolution. One early GOP plan placed it at six weeks – basically until Thanksgiving, which Reid insisted wasn’t long enough. A proposal floated by Sen. Susan Collins (R-Maine) would have extended the continuing resolution for six months.