Everything about the debt-ceiling process has become nerve-wracking. Will Republicans crash the economy? Will President Obama give away the store? How soon will markets panic?

But intensifying the drama is that darned ticking clock.

A few weeks ago, White House officials told congressional leaders that waiting to the last minute, or even the last week, for a debt-ceiling agreement wasn’t a viable option. The cutoff date — the date circled on the calendar as the day a deal must be complete in order to meet the deadline — was July 22.

That, as it turns out, happens to be today. And in case this isn’t obvious, the odds of wrapping up an agreement today aren’t especially good.

So, where does that leave us with regards to the inflexible calendar? As of a couple of days ago, the plan looked relatively straightforward: the House passes Cut, Cap, and Balance; the Senate defeats Cut, Cap, and Balance; the Senate starts the clock on the McConnell/Reid Plan B compromise; the Senate passes Plan B; the House whines about Plan B; the House passes Plan B anyway; and President Obama signs Plan B. Disaster averted.

As of this morning, the course is far less clear. The Senate will defeat CC&B, probably today. The McConnell/Reid Plan B is reportedly done, and ready to be introduced, though all of the details have not yet been shared. But the Gang of Six is still making noises about trying to get its plan into legislative form in time for Aug. 2; House Republicans are still making noises about rejecting Plan B and the Gang of Six; and the White House is still trying to persuade Democrats to support a Grand Bargain that, by most accounts, is pretty awful.

“That,” Brian Beutler reports this morning, “leaves us at crunch time.”

After Friday’s symbolic vote on Cut, Cap, and Balance, the President and Congressional leaders will have about 48 hours to announce a deal that can pass both Houses. If that doesn’t happen, Reid will file cloture on a fallback plan — Plan Z — he’s negotiated with Mitch McConnell to avert catastrophe. According to top Senate Democratic and Republican aides, that plan’s largely written, sitting on a shelf, and ready to go if the prospects for a bigger deal diminish.

If Senate conservatives do all they can to delay Plan Z, it could take the Senate until Friday to pass it. And if the House adheres to its own rules, which requires legislation to be publicly available for 72 hours before a final vote — the debt limit bill won’t be ready for the President to sign until a week from Monday, one day before Treasury’s drop-dead date August 2.

Reid would be able to pause that plan if a bigger deal manifests between now and the middle of next week. At that point legislators could pass a days-long extension of the country’s borrowing authority while the grand bargain was drafted, scored, and put to a vote. But he has to set things in motion imminently, or the government will reach August 2 empty handed.

Tick tock.

Steve Benen

Follow Steve on Twitter @stevebenen. Steve Benen is a producer at MSNBC's The Rachel Maddow Show. He was the principal contributor to the Washington Monthly's Political Animal blog from August 2008 until January 2012.