For months, the argument over an increase in the nation’s borrowing limit seemed to founder on the failure to agree on the big stuff — curbing spiraling Medicare costs, how deeply to cut military spending, how to raise more tax revenue without raising tax rates. But now that the political realities have forced those ambitions into retreat, the latest plans seem no more promising for being made up of small ideas instead of big ones.

After a difficult weekend of negotiations between the White House and top congressional leaders, legislators return Monday to Washington with no clear way forward to raise the $14.3 trillion debt limit before the Aug. 2 deadline.

Congress and President Obama are finding that a limited deal is no easier than a grand one.

It now appears that Republicans in the House could push forward with a proposal to cut the debt by $1.2 trillion now and raise the debt ceiling only enough to give the government the borrowing authority to spend for just a few months.

They would return to deeper cuts and a more significant hike in the borrowing limit later.

The Senate could put forward a divergent plan that would give Obama the $2.5 trillion hike in the debt ceiling he has sought, pairing it with equivalent spending cuts but no new revenues.

Neither plan would involve the kind of debt reduction or solution to vexing problems both sides once sought. The evolving proposals largely push off the hardest issues, perhaps handing them to a 12-member legislative commission charged with devising entitlement and tax code changes by Dec. 31.

Still, there is no agreement on how to move forward on the remaining issues.

If the House and Senate proceed as planned with competing proposals, neither would have a sure shot at passage in the originating chamber — and they would face a more serious chance of failure in the opposite.

“There’s a certain insanity in this,” said Steve Bell, a former Senate Republican aide who is now senior director of the Bipartisan Policy Center’s economic policy project. “It seems like we’re now into musical chairs, of who’s going to be the last one without a chair at the end and get the blame. And when you’re into the machinations of who gets blamed, there’s an assumption that something blameworthy is going to occur.”

Timing is key

In the House, Republicans who took charge last year promising a new era of transparency have said they will not force votes on legislation that has been public for less than three days.

Unless they reverse themselves on this new rule, the earliest the House could pass a bill would be Wednesday.

A bill approved by the House that day would then take at least four to six days to make its way through the Senate.

That timeline would conceivably allow a bill to reach Obama by the deadline — but only if there were agreement in both chambers, and so far there is none.

A bill that starts in the Senate might not pass until Friday, setting up a final showdown vote in the House next weekend.

The key point of contention now appears to be one of timing that, until now, did not appear to be terribly troublesome — whether the debt ceiling should be raised enough that Congress would not have to vote on the issue again before the 2012 election.

Members face a maelstrom of outside pressures that will make action more necessary and more difficult as the days slip by.

Most notable will be the Monday opening of the markets, which are widely expected to take nervous note of the lack of progress.

But partisans on both sides will also face unprecedented threats from their supporters not to give away too much.

Republicans almost universally report they are hearing from constituents that they should fight on.

Last week, a representative of the Tea Party Patriots visited the offices of House freshmen with a blunt message: Don’t raise the debt ceiling, no matter what.

“We have been telling them to hold firm. Our organization has been saying do not raise the debt ceiling at all,” said Jenny Beth Martin, who delivered the Tea Party Patriots message.

Thirty-nine House Republicans have promised not to vote to raise the debt limit without a plan, already killed by the Senate, to link the hike to passage of a new constitutional provision requiring balanced federal budgets.

“The core question for the president is, will he support a balanced-budget amendment?” Rep. Jason Chaffetz (R-Utah) said Sunday. At the same time, liberals remain deeply wary that deep cuts in programs for the needy and no taxes on the rich will be the outcome of the talks. Eighty Democrats have signed a letter promising to oppose such a deal.

‘No’ votes lining up

“There’s an assumption that at the end we have to go along. I think that is a political miscalculation on the part of the White House,” Rep. Raul M. Grijalva (D-Ariz.), chairman of the House’s progressive caucus, said late last week. “I hope there’s not a litmus test: ‘Are you for the president or not?’”

The liberal group is calling on its members to protest at every congressional office in the country on Tuesday at noon by calling for a deal that does not cut Medicare benefits or Social Security.

“Our core message to Democrats has been: ‘You promised not to cut Social Security and Medicare. Stick by that and we’ll stick by you,’ ” said Justin Ruben, the group’s executive director.