If Congress somehow pulls back from the brink of lunacy (as rumored today), if it forges a deal to reopen the government and keep paying Uncle Sam's bills (as rumored today), lots of tea party conservatives are likely to scream betrayal and threaten to quit the Republican party.

Sane Republicans can only hope so.

David Frum, the former George W. Bush speechwriter who has chronicled the conservative movement since the early '90s, is one guy who dearly pines for a tea party divorce. Some tea partyers have indeed been talking up the idea of a "third party," and Frum would love to see it happen:

"Right now, tea party extremism contaminates the whole Republican brand. (A split would) liberate the party to slide back to the political center - and liberate Republicans from identification with the Sarah Palins and the Ted Cruzes who have done so much harm to their hopes over the past three election cycles...Maybe the right answer to the threat, 'Shut down the government or we quit' is, 'So sad you feel that way. Don't let the door hit you on the way out.'"

Various pundits agree that a tea party exit would be a great way to save the GOP. Economist Daniel Altman writes, "A reinvigorated Republican party, under the banner of centrists like Chris Christie and Rob Portman, would no longer have its low-tax and small-government messages polluted by anti-gay, anti-immigrant, and anti-poor rhetoric. Such a party might even gain enough seats in swing and Democrat-held districts to replace the far-right votes it had lost."

And The Economist magazine lists reasons why tea partyers would be happy to go: "Their voting base already detests the Republican leadership, and would likely follow them if they rebelled. They have powerful organizations, both at the grassroots level and in the big-donor astroturf world of the Koch brothers. They share a coherent ideology." All told, "tea party Republicans would have a better shot at launching a sustainable third party than we've seen in America in a long time."

We'll see about that. If tea partyers go ballistic over a compromise deal that ends the shutdown and cures the debt default crisis, they're still not likely to bolt the GOP en masse - because the movement is not monolithic. Some of the grassroots groups, which define themselves as conservatives first and Republicans second, might indeed weigh such a move (as they have threatened before), but some of the fake-grassroots groups, like FreedomWorks and Tea Partry Express, are run by traditional Republican strategists who would never leave the party. (They'd rather stay, drive the party further rightward, and plunge the party's national approval rating to new historic lows.)

But some tea partyers are likely to threaten a walkout, because it's clear that their Republican leaders have no stomach for sustaining a shutdown or precipitating a global financial crisis. The delusional tea party dream of holding the nation hostage until President Obama agreed to gut Obamacare - that ain't happening.

The Senate has sketched a bipartisan plan that mostly nibbles around the edges of Obamacare (new steps to verify the incomes of people who apply for coverage subsidies; a one-year delay of a tax aimed at helping insurers who cover lots of sick people), and, naturally, the House's tea party gang calls that a surrender. Worse than a surrender, actually. One top tea partyer calls it "a mushy piece of s---t."

It's like they're all wearing a T-shirt that says, "We crashed the government, got people laid off, threatened an international economic crisis, and all we got was this lousy T-shirt."

So now, as the clock continues to tick toward global doomsday (the Deutsche Bank says that a U.S. debt default would be "a rapidly spreading fatal disease"), House Republican leaders are trying to conjure settlement terms that can somehow satisfy the Senate's Republican grownups, the Senate's Democratic majority, the Obama White House, and, of course, the tea party gang.

Good luck mollifying the latter. As a spokesman for the Tea Party Patriots warns, "If (Republicans) walk away from the current situation without securing any real, meaningful relief from Obamacare, we're going to be very upset with them."

But would they be upset enough to bolt the party? Sane Republicans should be so lucky.

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