Speaker Nancy Pelosi and her deputies had planned to reach a deal on a stopgap spending bill with Republicans by Wednesday morning, allowing both chambers to quickly approve the measure and avoid a funding lapse by midnight Friday. But the House will not vote Wednesday on a funding fix, according to senior Democrats, which gives party leaders just two fraught days to avert a shutdown — even a brief one. If a deal is reached, the House Rules panel could still meet Wednesday night, teeing up quick action on Thursday to send a bill to the Senate.

Complicating matters further, the Senate is locked in a stalemate over the annual defense policy bill, leaving the chamber little floor time to process a stopgap spending bill before the weekend.

House Appropriations Chair Rosa DeLauro (D-Conn.), who has been publicly and privately confident that she can clinch a shutdown-averting deal with GOP leaders, seemed exasperated as she entered the House chamber Wednesday afternoon.

“We’re still waiting. Still waiting,” she said. “Let’s keep some optimism.”

Those sudden setbacks are now threatening to blow up one of Congress’ most important priorities this month and one of its fundamental tasks. And the rising tension is raising huge concerns across the Capitol about what’s in store for the rest of a dreaded December jammed with deadlines likely to be a lot more painful than simply extending current government funding.

“The stonewalling on the omnibus is one thing, but this? One would hope we would lock arms and at least avoid a shutdown,” said Rep. David Price (D-N.C.), a senior member of the House spending panel. “And today is the day we need to do the House bill.”

Still, with the Senate floor sitting idle amid negotiations over the defense measure, Republicans might be able to run out the clock before Friday night, denying adequate floor time to consider a funding bill. Senate leaders were still negotiating Wednesday afternoon over a package of amendments to the defense legislation, with a small group of Republicans insisting on additional amendment votes.

One of the biggest holdups over the stopgap funding measure: exactly how long it should last.

While Democrats are eyeing a date through late January, Republicans have insisted on a longer timeline for the spending bill — known as a continuing resolution — eager to stick their opponents with Donald Trump-approved spending levels for as long as possible.

“Republicans should be in favor of CRs until Biden is out of office,” said Texas Republican Rep. Dan Crenshaw. “That would be the proper Republican thing to do and anybody saying otherwise is deeply foolish.“

GOP leaders insist that more time is needed to negotiate a broader bipartisan funding deal — the first of Joe Biden’s presidency. Democrats, meanwhile, argue that the longer they operate under a stopgap, the less likely lawmakers will be able to agree on a full year bill under Biden-era funding levels.

“There is a good conversation to be had about what the length of that is and whether we’re just setting Democrats up to pass much worse bills,” Crenshaw said.