Site: House.govSite: House.govAfter weeks of resistance, and mounting pressure from House conservatives, Speaker of the House John Boehner has agreed to put a continuing resolution that funds the government—but doesn’t fund Obamacare—up for a vote.

It’s a fallback option after House leadership’s earlier plan fell through. Boehner had initially planned to introduce two continuing resolutions: one that defunded the health law, and one that didn’t.

That would have allowed House Republicans to say they voted to defund Obamacare. But it would also allowed the Senate, which is controlled by Democrats, the option to essentially pick which bill they wanted to pass—with the clear understanding that the bill that included Obamacare funding would win the vote. The two-bill plan also would have helped Republicans reduce the risk that they lose the spending restraint won through the sequestration process by giving Senate Democrats the option to pass a funding bill that kept spending for Obamacare in place but also left existing spending reductions in place.

But instead of the two-bill plan, the House will now simply vote on—and presumably pass—a single bill that keeps sequestration spending levels and defunds Obamacare. That bill will go to the Senate.

And at that point Senate Democrats are virtually certain to strike the Obamacare defunding provisions, and perhaps increase overall spending levels as well. The new, Senate-altered bill will return to the House for a vote. If no continuing resolution is passed and signed by September 30th, then it’s time for a government shutdown.

The big open question here is what happens when Senate Democrats do what they are all but guaranteed to do, and ditch the Obamacare defunding business in the House resolution. Do House Republicans back down, and agree to pass a funding plan that includes funding for Obamacare? Or do they hold the line, shut down the government, and try to win a standoff with Democrats by arguing that Democrats are holding up essential government functions in order to preserve an unpopular health law? It’s a long shot plan, at best. The shutdown itself wouldn’t be enough to stop Obamacare’s implementation. And despite Obamacare’s lack of public support, neither the polls nor the history weigh in the GOP’s favor should such a showdown occur. But they may try anyway. We’ll know for sure soon enough.