The good news is that the federal deficit is steadily shrinking—the goal both sides say they share as common ground. But that's where consensus begins and ends.
"The lower deficit certainly will take the pressure off immediate action," said Bixby. "But it doesn't really change the difficult choices that Congress is going to have to make fairly soon. It just changes the mood music and the atmosphere."
For the current fiscal year, which began in October, the federal government's spending gap has narrowed by more than a third, dropping to $607 billion from the $974 billion in red ink during the same period a year earlier. As the economy has grown, the deficit as a percentage of gross domestic product has fallen even further.
Part of the improvement comes from this year's compromise package of tax hikes and spending cuts, which slowed the growth of federal spending by $85 billion (and it is set to trim another $20 billion for the next fiscal year beginning in October.)
The debate on extending those cuts will be colored by this fall's data on the U.S. economic recovery, which most analysts agree has been held back somewhat by tighter federal spending. The Congressional Budget Office recently estimated that canceling the 10-year austerity measure would increase federal spending by $104 billion through fiscal 2014, adding roughly 0.7 percent to annual GDP growth and spurring creation of an additional 900,000 jobs.
Tax increases and spending cuts, though, account for only part of this year's smaller deficit. The rest was a series of more or less of lucky breaks, including a series of one-time windfalls that were hard to see coming.
The Treasury enjoyed something of a windfall, for example, from a surge in taxes late last year as investors sought to book profits before this year's increase in the capital gains tax rate. Uncle Sam also benefited from a surprise, one-time dividend from mortgage giants Fannie Mae and Freddie Mac, which the government bailed out after housing bust and had all but left for dead.
All of these factors have helped shrink the deficit in the short term. But deficit watchdogs say they're the budgetary equivalent of finding quarters and dimes under the couch cushions.
"We haven't really shrunk government so far," said Marc Goldwein, senior policy director of the Committee for a Responsible Federal Budget. "What we've done is furlough people and found ways to defer and delay payments and investment and found hidden money in accounts. That's not a sustainable strategy."
There's also been little progress in fixing the political machinery that relies on budgetary brinksmanship to reach agreement. Even if a budget deal is reached by Sept. 30, Congressional crisis-lovers will get another chance at chaos in November, when the government is once again set to reach its legal borrowing limit known as the debt ceiling.
The exact date is unclear. If the economy picks up speed this fall, for example, that would boost tax receipts and postpone the day the government hits its current $16.7 trillion credit limit. The Treasury also has some cash management juggles that could postpone the day of reckoning as the deadline approaches, but not for very long.
(Read more: Global CFO Council survey: US economy holding the line)
Two years ago, when deficit hawks in Washington threatened to send the U.S. Treasury on a path to default, the backlash from the financial markets helped shape a last-minute deal. That self-inflicted crisis —and the prospect of it happening again—cost the U.S. government its Triple-A credit rating.