What looked last week like a game of political hot potato has become a high-stakes game of chicken, with continued operation of the federal government and possible wider impact on the overall economy hanging in the balance.
In a move that makes a shutdown appear very likely, House Republicans approved a spending plan early Sunday morning that would delay the Affordable Care Act for a year and repeal its tax on medical devices.
The temporary budget resolution now goes back to the Senate, where Democrats have consistently said any changes to President Barack Obama's signature health care law would be a deal-killer.
On top of that, Obama has already issued a veto threat.
If Washington can't reach a deal, a government shutdown will begin at 12:01 a.m. Tuesday.
Congress could avert a shutdown by passing a temporary spending measure while the two chambers work out their differences.
Senate plan for Monday
"Tomorrow, the Senate will do exactly what we said we would do and reject these (House) measures," Adam Jentleson, spokesman for Senate Democratic Leader Harry Reid, said in a statement issued Sunday evening. Jentleson continued, "At that point, (House) Republicans will be faced with the same choice they have always faced: put the Senate's clean funding bill on the floor and let it pass with bipartisan votes, or force a Republican government shutdown."
A Senate Democratic leadership aide told CNN that on Monday the Senate will take one simple majority vote to table the various parts of the House bill with which the Senate Democratic majority disagrees. Then the Senate plans to send the same funding bill -- a bill without any changes to Obamacare -- back to the House that the House's Republican majority rejected very early Sunday morning.
This game plan avoids taking a separate vote to reinstate a controversial tax on medical devices that is repealed in the House bill. The medical devices tax has become a target of the House GOP because some Democrats do not support it three years after Obama signed the health care law.
The same aide also said that he fears House Republicans will force a shutdown of a few days before they ultimately accept the Senate's version of the funding bill. The aide noted that Democrats had already compromised in the Senate version of the funding bill by accepting a lower funding level than they wanted.
The aide had no knowledge of or expectations for any last-minute negotiations with the White House or anyone else to resolve the stand off.
House GOP leaders defiant
As the countdown to a shutdown marched on, House Republican leaders remained defiant Sunday in their effort to chip away at Obamacare.
"If the Senate stalls until Monday afternoon instead of working today, it would be an act of breathtaking arrogance by the Senate Democratic leadership," House Speaker John Boehner said Sunday afternoon in a written statement. Boehner added, "I call on the Democratic leaders of the Senate to act today on the measure passed by the House last night."
House Majority Whip Kevin McCarthy, R-California, one of Boehner's top lieutenants, said Sunday that if the Senate rejects the latest House bill, House Republicans will send the Senate another bill that both funds the government and contains provisions regarding Obamacare.
"I think the House will get back together -- in enough time -- send another provision, not to shut the government down, but to fund it," McCarthy said on "Fox News Sunday," "and it will have other options in there (about Obamacare) for the Senate to look at again."
"We are not shutting the government down," McCarthy insisted when asked whether he was willing to risk the first shutdown of the federal government since 1996. "While the president was out golfing (Saturday) and the senators went home, we were here working till 1 a.m. to make sure we didn't shut the government down, that we put a funding bill across."
Asked whether the House would consider passing a funding bill without any provisions regarding Obamacare and with votes from House Democrats, McCarthy would not commit to that course of action and, instead, said again that the next bill the House passes will address Obamacare in some way.
McCarthy did, however, leave open the possibility of a stopgap funding measure that funded the federal government for a few days in order to avoid a shutdown.
"We will not shut the government down," McCarthy said. "If we have to negotiate a little longer, we will continue to negotiate."
"We do not want to shut the government down," McCarthy added.
Boehner's and McCarthy's focus on House GOP efforts to avoid a shutdown by working late into the night Saturday were echoed by Rep. Cathy McMorris Rodgers, chairwoman of the House GOP Conference.
"We were there almost till midnight last night, working on the bill, passing the bill, got even some Democrat support in the House, and yet the Senate won't even come back today," McMorris Rodgers, of Washington state, said Sunday on CNN's State of the Union.
"They're the ones playing games," she continued. "They need to act. They're the ones that are truly threatening a government shutdown by not being here and acting."