For two months now, 12 members of Congress have sat in a windowless room stocked with granola bars and two coffeemakers, trying to remember how Congress is supposed to work.

So far, no luck. And time is running short.

The job of the congressional “supercommittee” — charged with cutting $1.2 trillion from the country’s deficit — is to rekindle the possibility of the great big bipartisan deal, made by the big wheels in Congress.

But now, it seems, nobody is big enough.

One major reason for the committee’s struggles is that members are often strangers to one another, carrying little of the personal trust that made previous deals possible. And even the most powerful leaders are weaker than past bosses — uncertain that their party will follow if they try to lead.

Now, the supercommittee has only nine days to re-create the past.

“The principals have to have trust in one another,” said Bob Bixby, executive director of the Concord Coalition, who watched past budget deals come together. “They have to go into it with a willingness to compromise, and that means listening to each other’s concerns and getting a feel of what is really non-negotiable.”

Not happening.

“That’s clearly not the dynamic that we have going on right here,” Bixby said.

The supercommittee, made up of six Democrats and six Republicans, is immersed in the congressional equivalent of an arranged marriage, trying to create intimacy where there was none.

Sens. Rob Portman (R-Ohio) and John F. Kerry (D-Mass.) have gone on morning bike rides together. Kerry has shared some of his favorite foods with the group, bringing in Georgetown Cupcakes and Legal Sea Foods clam chowder. Late at night, when the group has gathered to gab in her office, Sen. Patty Murray (D-Wash.) has reminded them that her desk was a gift from a Republican lawmaker. (In the Capitol, where furniture is handed down over decades, great value is attached to the provenance of desks.)

“We’ve been able to conduct our business in an appropriate way, let’s put it that way, rather than banging fists on the table, walking out of meetings. None of that’s happened,” Sen. Jon Kyl (R-Ariz.), one of the 12, said last week.

So they have achieved decorum. But not much else. Nothing like the great bipartisan bargains that are now Capitol Hill’s campfire stories — legendary deals cut by leaders who felt strong enough to compromise.

In 1983, for instance, Congress was stalemated on how to fix a funding problem that threatened Social Security. A bipartisan committee had gone nowhere. On the Senate floor, Sen. Daniel Patrick Moynihan (D-N.Y.) tapped Sen. Robert J. Dole (R-Kan.) on the shoulder and said 14 words: “Are we going to let this commission die without giving it one more try?”

The two sides then worked out a compromise that included benefit cuts and tax increases.

This year, a similar bargain has proved elusive. Some would argue that part of the reason is that there are too few Moynihans or Doles left.

“As much as probably most of the group would want to get something done and help save the country’s economic future, there is a Republican fear of [anti-tax activist Grover] Norquist and the tea party base,” said a Democratic aide familiar with the talks. “There is a Democratic eagerness to preserve things that matter to us,” meaning programs such as Medicare and Social Security.

What does it add up to?

“Nobody’s empowered” to strike a deal, the aide said.

That was made obvious Monday, as some conservatives criticized the supercommittee’s Republicans for an offer that included about $300 billion in new taxes. The message was obvious: Those six don’t speak for us.

“I’m not voting to raise taxes,” said Rep. Jason Chaffetz (R-Utah). Support from conservatives such as Chaffetz could be crucial next month, since the full House and Senate would need to approve any plan that the supercommittee came up with.

For many outside observers, this outcome was easy to predict. First of all, the leaders of the two parties — President Obama and House Speaker John A. Boehner (R-Ohio) — had made their own effort at reaching a “grand bargain” over the summer. That failed, as both came under fire for giving away too much in the offers.

The supercommittee was supposed to succeed where they failed. But its two co-chairs obviously have less heft to throw around.

When Rep. Jeb Hensarling (Tex.) questioned Obama sharply at a GOP retreat in early 2010, the president’s response hinted that Hensarling was not a dominant figure in Washington. He called Hensarling “Jim” — three times.

Murray, the other co-chair, had already signed on to chair the Democrats’ Senate campaign effort for 2012. That may erode her ability to gain the trust of Republican colleagues.

In addition, Murray and Hensarling had never met, despite having served together in Congress since 2003. Aides said that they, and other members of the committee, have tried to build relationships quickly, which has meant hours and hours of getting-to-know-you-and-your-policy-views time.

That time is almost up. The supercommittee must produce a plan by midnight next Wednesday. On Monday in Room 200 — the wood-paneled room where 12 legislators are supposed to make Congress act like Congress again — there were empty chairs and a tray full of uneaten GoLean granola bars and Craisins.

All over the Capitol, supercommittee members were meeting in small groups, trying to agree on some small piece of a large compromise. But on both sides, there were signs that the primary precondition of a great big deal was breaking down: Democrats and Republicans were losing faith that the other side wanted to fix this mess as badly as they did.

“Republicans embrace this mess, because at that point Washington is a broken place that only gets fixed by getting rid of incumbent members,” a Democratic aide said. “You can see it, feel it and hear it.”

Said a Republican aide, talking about Democrats: “It seems like they’re kind of running out the clock.”

Staff writer Rosalind S. Helderman contributed to this report.