House leaders’ best-laid plans for an orderly kabuki to avert a government shutdown have once again been upended by insurgent conservatives, increasing concern about the potential for a government shutdown less than two weeks from now.

The decision to tie Obamacare funding to must-pass legislation keeping the government open was a turnabout for Speaker John A. Boehner, R-Ohio, who had quietly resisted the idea for years.

It’s the latest humbling of a leadership team that has continually struggled to corral its own party. But it’s not clear yet whether it will cost the GOP leverage with Democrats.

Boehner’s decision to craft a bill designed to get 218 Republican votes should unify his party — for a week, at least.

“It gives everyone everything they want: it defunds Obamacare, locks in the sequester savings and it avoids a government shutdown,” one senior GOP aide said of Boehner’s reworked strategy.

But it isn’t a plan with any real expectation of becoming law. The two chambers appear headed to the same place they would have likely ended up anyway, with merely a detour to appease Boehner’s conservative wing — a CR that keeps the government open at Boehner’s $986 billion level through Dec. 15. But getting there will now require a potentially messy set of votes in the Senate and a return trip to the House — which means the brinkmanship could push up against the deadline.

Democratic aides said Senate Majority Leader Harry Reid, D-Nev., will need to find a handful of Republican votes to overcome a filibuster of a CR that doesn’t roll back Obamacare. And while some liberals might want Senate Democrats to attach their preferred, $1.058 trillion spending level and nuke the sequester spending cuts, Democratic aides see the lower level as the far easier political play, lest they get tagged with risking a shutdown themselves.

On the flip side, Republicans in the Senate seem to be split over whether the bill should defund Obamacare or just come in at the lower $967 billion threshold demanded by the sequester.

White House Press Secretary Jay Carney has repeatedly indicated that the president could accept a short-term stopgap CR, and the administration has not yet demanded a specific funding level. Presumably, the administration and Reid will work in tandem to get a bill through.

A final bill would then come to the House floor, with enormous pressure on both parties to pass it to avoid a shutdown.

Republicans would face pressure from the right over the lack of Obamacare defunding; Democrats would face pressure from liberals upset over the failure to replace the sequester.

And while Boehner and his allies in the House have pointed to the Senate as the next battleground over Obamacare, Republican senators allied with the tea party continue to pressure Boehner.

“Harry Reid will no doubt try to strip the defund language from the continuing resolution, and right now he likely has the votes to do so,” said Sen. Ted Cruz of Texas in a statement. “At that point, House Republicans must stand firm, hold their ground, and continue to listen to the American people. President Obama has already granted Obamacare exemptions to big corporations and Members of Congress; he should not threaten to shut down the government just to deny those same exemptions to hard-working American families.”

In response, Boehner spokesman Michael Steel put the onus on Senate Republicans.

“We trust Republicans in the Senate will put up a fight worthy of the challenge that Obamacare poses,” Steel said.

Boehner has repeatedly sought to avoid government shutdowns over the past two years, and said he wanted to avoid one again.

“There should be no conversation about shutting the government down,” he said Wednesday. “That’s not the goal here.”

Still, GOP aides were cagey Wednesday about whether Boehner would even allow a straight up-or-down vote on any “clean” CR the Senate sends him.

Even if Boehner finds the votes to send a clean bill to the president’s desk, that can-kick would only resolve one of the twin self-imposed crises facing the Capitol, given that House Republicans are piling up ransom demands in return for raising the debt ceiling. Their wish list includes a one-year delay in Obamacare and approval of the Keystone XL oil pipeline.

Obama reiterated Wednesday that he will not negotiate on the debt ceiling and urged CEOs at the Business Roundtable to use their influence with Congress to get Republicans to back off their threats.

“I am prepared to work with Democrats and Republicans to deal with our long-term entitlement issues,” he said. “What I will not do is create a habit, a pattern, whereby the full faith and credit of the United States ends up being a bargaining chip to set policy. It’s irresponsible.”

A few hours later, the Chamber of Commerce issued a statement urging Congress to increase the debt ceiling without delay.

Republicans, however, pointed out that Obama himself voted against a debt ceiling hike and note that debt bills have, in the past, been an impetus for other budget deals.

“Every major deficit deal in the last 30 years has been tied to a debt limit increase, and this time should be no different,” Boehner spokesman Brendan Buck said.

House leadership also plans to include a provision in the CR that would prioritize debt payments to avoid defaulting on interest owed on bonds.

But the brinkmanship has alarmed Senate Democrats.

“I’m more worried about default than I’ve ever been,” Sen. Charles E. Schumer, D-N.Y., told reporters at a news conference to discuss the economic costs of the uncertainty on the debt limit.

Senators on the Finance Committee huddled with Treasury Secretary Jacob J. Lew who warned against delay. Carney dismissed a Republican lawmaker who said the party is doing what its constituents want.

“My question to him would be, will they be for it when in the wake of devastation of default, they can say, ‘Well, I don’t have a job because the economy’s cratering, but thank God you’ve taken away my opportunity to buy health insurance?’ I doubt it.”

Meredith Shiner and Emma Dumain contributed to this report.