There are 233 Republicans in the House. Insiders estimate that three-quarters of them, or about 175 GOP lawmakers, are willing, and perhaps even eager, to vote for a continuing resolution that funds the government without pressing the Republican goal of defunding or delaying Obamacare.

On the other side, insiders estimate about 30 House Republicans believe strongly that Obamacare is such a far-reaching and harmful law that the GOP should do everything it can --- everything --- to stop it or slow it down. That includes precipitating a standoff leading to a government shutdown. "This isn't just another bill," Rep. Michele Bachmann, R-Minn., one of the most vocal of the 30, told me. "This isn't load limits on turnip trucks that we're talking about. This is ... an extremely consequential bill that will impact every American, and that's why you have such passionate opinions."

Another 20 to 30 GOP members sympathize with that position but might be willing to compromise, except for the fact that they fear a primary challenge from the Right.

In the continuing resolution fight, it is the 30 most committed members, along with their 20-30 allies in the next-most-committed group, who are setting the House Republican agenda. The ones pushing for a fight over Obamacare, even if it leads to a shutdown, are controlling what the House does.

Which has led to the question: How can 30 Republicans beat 200 Republicans? How does that work?

There are two answers. One, the Republican majority in the House is fairly narrow. And two, Democrats have been extraordinarily unified in opposing GOP proposals.

It takes 217 votes to pass a bill in the House. Republicans can pass one all by themselves, but only if they keep 217 out of the total 233 GOP lawmakers on board. If more than 16 GOP lawmakers jump ship, Speaker John Boehner won't have enough Republican votes to pass any given bill.

That's where Democratic unity comes in. There are 200 Democrats in the House. If they unanimously oppose a bill, then Boehner has to keep almost all of his GOP lawmakers together, or the measure will fail.

The combination of those two factors --- a close Republican majority and united Democratic opposition --- gives those 30 Republicans their power. In a situation where Democrats nearly unanimously oppose a bill, the 30 can make the difference between success or failure for Boehner. If they stick together, Boehner can't win.

That's the Democrats' goal. "Hoyer has done a remarkable job in sustaining Democratic discipline," says a well-connected GOP strategist, referring to House Minority Whip Steny Hoyer. "He says every day, 'If we Democrats stick together, we let those 30 [Republicans] run the House, or have a huge say that they wouldn't ordinarily have.'"

It's been a devastatingly effective strategy, and it has helped create a deep and growing frustration inside the GOP conference. Just look at what a member of the Republican majority told me after House Republicans had taken another step toward confrontation. "Analysts say the Congressional GOP doesn't understand strategy," the Republican said. "I'm like, 'Congressional GOP' my ass! It's 30 idiots who can't get us to 217."

Boehner tries to walk a delicate line within his conference. But the chances are good that in the end, the majority of Republicans --- the 200, or at least 175 --- will take control. If Boehner offers them a "clean" continuing resolution, they will vote for it.

When Rep. Raul Labrador, R-Idaho, one of the Republicans committed to defunding or delaying Obamacare, appeared on "Meet the Press," he was asked whether he was willing to vote for a resolution that funded the government but did not touch Obamacare. "I am not," Labrador answered. "But I think there are enough people in the Republican Party wiling to do that. And I think that is what you are going to see."

When the time comes, lots of Democrats will vote for the resolution, too, which means the final spending measure, when it finally comes, will likely pass with a big majority.

But Republicans aren't there yet. "This is a process that Boehner is going through to get to that point," says the GOP strategist. The speaker has bent over backwards to give the most committed members of his party their say. After another defeat or two, and under the pressure of a shutdown, Boehner will finally turn to the 30 and say, "We tried it your way, over and over. Now, the majority will pass a resolution."

At that moment, the crisis will be over. At least for now.