Rep. Chris Van Hollen (D-Md.) told reporters on Wednesday that a final vote on legislation extending several measures would be difficult.
"We're working to try and pass it as soon as possible," he said.
A chief hurdle to getting the needed votes in the House is securing 60 votes in the Senate, a goal that appears out of reach.
"That remains an important issue," Van Hollen said. "Our members want adequate assurances from the Senate that they will pass this bill in its current form. That has been one of the impediments to moving it."
Democratic leaders are looking to shrink the size of the bill, which costs approximately $200 billion. But Van Hollen discounted the idea of reducing the "doc fix," or shortening the expansion of the unemployment insurance or CORBA.
"It is my knowledge that they will remain the same," he said, but cautioned that the bill remains a work in progress.
"I have to tell you, around here, to be current on this particular issue, you have to know what happened 10 minutes ago."