At last count, the House needs at least 20 votes to advance the bill to the Senate, where its fate is equally uncertain.
Lackluster support for the bill, which costs roughly $200 billion, is blamed on the approximately $140 billion it will add to the deficit, as well as its increased tax on businesses, which could hinder job creation at a time when the economy is just beginning to recover.
"We don't want to cut off our nose to spite our face and have a job creation bill turn into a job destroying bill," Rep. Jared Polis (D-Colo.) told The Hill. "There is vast support in our caucus for Build America Bonds and summer jobs that is in the bill. It's just a question of how we pay for it."
A chief pay-for in the bill is a tax increase on carried interest, which Polis argues will hurt job creation.
Democrats in both chambers are also concerned about the spending side of the bill, in particular the 'doc fix' that would delay cuts in Medicare payments to physicians. The provision cost $65 billion and is not paid for.
"I would like it to be paid for," Sen. Claire McCaskillClaire McCaskillFive takeaways from the Georgia special election Picking 2018 candidates pits McConnell vs. GOP groups Potential McCaskill challenger has .7M: report MORE (D-Mo.) told reporters.
The expense of the doc fix has so far kept some Senate Democrats from supporting the bill.
"I'm not a definite yes at this point," said Sen. Mark UdallMark UdallPicking 2018 candidates pits McConnell vs. GOP groups Gorsuch's critics, running out of arguments, falsely scream 'sexist' Election autopsy: Latinos favored Clinton more than exit polls showed MORE (D-Colo.). "I do think that we have to work double-time to pay for the extenders that are in the bill."
Still, despite the uncertainty of the bill's fate, Senate Majority Leader Harry ReidHarry ReidDraft House bill ignites new Yucca Mountain fight Week ahead: House to revive Yucca Mountain fight Warren builds her brand with 2020 down the road MORE (D-Nev.) expects the House will deliver the bill to his chamber before the end of the week. Other lawmakers are skeptical.