(CNN) The conventional wisdom -- even as senators flailed and failed to find a deal to keep the government open late Friday night and Saturday -- was that this would all be over soon.

The disagreements were real between the two parties, but the desire to look competent in the eyes of the public would bring warring lawmakers to the table. If the Senate only had a few more hours after the midnight Friday shutdown, they would have made a deal!

And, they still might! After all, the relative pain -- politically and in real-world terms -- of a government shutdown doesn't truly kick in until Monday when everyone goes back to work. Which makes Sunday a critical day for all sides involved in the shutdown. (The next scheduled vote in the Senate on the current four-week continuing resolution is Monday at 1 a.m. ET.)

But despite all of the assertions that a deal is in the offing, there isn't a deal yet. And the three-week continuing resolution that Sen. Lindsey Graham proposed late Friday night, which was seen by Republicans as the vehicle to end the shutdown, appears -- at least as of this writing -- to be dead in the water.

The case can be made, in fact, that if no deal gets done within the next 36-ish hours, this shutdown may go on longer than anyone in Washington expects.

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