They don't have a seat at the talks to defuse a year-end fiscal bomb, yet wield considerable influence.
They are wise-cracking debt-reduction duo Alan Simpson and Erskine Bowles; anti-tax activist Grover Norquist and Federal Reserve Chairman Ben Bernanke.
Bernanke, one of the first to use the term "fiscal cliff," warns repeatedly of the dire consequences of going over the precipice of across-the-board spending cuts and tax increases in January absent congressional action.
He has used the Fed's money-creation and interest-rate powers to help keep the economy on an even keel but warns there are limits: Congress and the president must step up to the plate.
Norquist has long extracted pledges from lawmakers to never raise any taxes. Some are chafing, but Norquist isn't budging.
President Barack Obama "doesn't have the mandate he thinks he does," Norquist says.
And Norquist is ready to work to drive from office those who violate "The Pledge."
Simpson and Bowles - chairmen of Obama's now-defunct deficit commission - have stoked the flames of fiscal reform with frequent public appearances.
Both Obama and House Speaker John Boehner call their proposals clear-eyed models for trimming government debt. But neither has embraced their painful proposals, including big changes to Medicare and Social Security, military cuts, new gasoline taxes and limits on home-mortgage deductions.
Yet Democrat Bowles says this could be the "magic moment" for a deal.
Obama visited a Falls Church, Va., family Thursday to highlight his call for raising taxes on top wage-earners a day after Treasury Secretary Timothy Geithner said the administration would "absolutely" go over the cliff absent a deal to raise top tax rates.
Simpson, a retired GOP senator from Wyoming, denounced "threats going back and forth, we're going to do this, we're going to go off the cliff..."
"There's stupidity in that," he told NBC's "Today" show. "What a nuthouse."
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