Will John Boehner break the Hastert rule and bring an immigration reform bill to the floor even if a majority of House Republicans oppose it? "It’s not gonna happen," he said Tuesday.

My colleague Greg Sargent thinks he's bluffing. And perhaps he is. But at this point, even Boehner doesn't know if he's bluffing or not. He doesn't know what his cards will be.

Will Boehner break the Hastert rule? Who knows? (AFP/Getty)

The first rule of the Hastert rule: It's not a rule.

The Hastert rule -- which states that the Speaker of the House won't bring legislation to the floor unless it's supported by a majority of his own party -- isn't actually a rule. It's more of an aspiration. Speakers follow it, except when they don't. It's a bit like my rule to jog every morning: I always follow it, except on the mornings when I don't.

There's a campaign right now among conservatives to make the Hastert rule a real rule. Dozens of conservative groups and luminaries sent a letter to House Republicans begging them to "formally pass the Hastert Rule that requires a 'majority of the majority' to pass legislation." Some conservative House Republicans have sent around a petition making much the same demand.

But most House Republicans don't want to make the Hastert rule into an actual rule. And the reason, as they'll tell you behind closed doors, is that it's not Boehner who breaks the Hastert rule. He'd never send a bill to the floor if a majority of House Republicans didn't want to see it on the floor. It's the House Republicans who break the Hastert rule. The reality of the House is that sometimes a majority of House Republicans want a bill to pass even if they don't want to vote for it.

They broke the Hastert rule to pass the "fiscal cliff" deal. Then they broke it again to pass an aid package after Hurricane Sandy. And then they broke it again when they passed the reauthorization of the Violence Against Women's Act.

There are good reasons Republicans break the Hastert rule

What all these bills had in common was that they presented Republicans with a collective action problem. It was better for House Republicans if the bills passed. But it was also better for a majority of House Republicans to vote against the bills. That might be because they oppose the bill ideologically or because they're worried about primary challenges or because they think their constituents will punish them. Whatever the reason, breaking the Hastert rule allows them to have it both ways: Republicans can vote against the bills, but the bills can pass anyway.

Three months before the fiscal cliff deal Boehner had no intention of letting a tax increase onto the floor that most of his members opposed. Same goes for Sandy aid, and the Violence Against Women's Act. In each and every case Boehner fully intended to find a proposal the majority of his members supported. But in the end the only proposal a majority of his members supported was the proposal to break the Hastert rule and pass the bill with Democratic votes.

No one knows if the Hastert rule will be used on immigration

Will immigration reform go the same way? That's certainly the dominant theory in the Senate, and it's fairly common in the House, too.

Here's how it would go: The Senate passes an immigration bill in July. Then the House passes a much smaller, much more conservative bill in, say, September. The two bills go to conference, and it quickly becomes clear that the House bill is dead in the water: It's going nowhere in the Senate, would be vetoed by President Obama, and is broadly loathed by the Hispanic community. After much huffing and puffing, the House and Senate emerge with something that looks more or less like the Senate bill, and Republicans, in order to protect the future of their party, decide to bring it to the floor and pass it with Democratic votes.

It may never come to that. "There’s a group of people in Republican conference opposed to all possible immigration legislation," says one House Republican aide. "That group is very vocal but they're somewhat smaller than people think. Most members are very eager and very curious to see what is actually introduced in the House."

But perhaps it will come to that. Perhaps a majority of House Republicans simply won't want to vote for any serious immigration reform bill. The question then is whether a majority of House Republicans nevertheless want to see such a bill pass. We won't know until we get there. And even if he is willing to break the Hastert rule, Boehner will never, ever, under any circumstances suggest that he'll break the rule until the very moment he does it. To open that as a possibility would rob Republicans of any leverage they have in their negotiations with the Senate.

Which is why the real test of whether the Hastert rule is a viable option is the conservative mobilization to encode it as a real, ironclad rule of the House. As long as House Republicans resist that effort, they're leaving open the possibility of breaking the Hastert rule during immigration reform's endgame. But we won't know if they're going to do it until we get to that endgame, because they won't know if they're going to do it until they get to that endgame.