The fate of a bipartisan budget agreement was in limbo hours before a Thursday night deadline to avoid a partial shutdown of the federal government, with Republicans and Democrats still at odds over spending levels and immigration.
Optimism about the $300-billion, two-year budget agreement began to falter as some House Democrats threatened to vote against the bill because it does not address immigration. Some conservatives are also threatening to vote against the measure because it would increase spending and add billions to the deficit.
Senate leaders had hoped to pass the bill early in the day but were forced to wait after Sen. Rand Paul, R-Ky., objected to the plan. Paul said he planned to force the Senate to wait until the early hours of Friday morning — after the midnight shutdown deadline — when debate time would expire and the Senate would be allowed to override his objection.
"I'm not advocating for shutting down the government," Paul said in an interview on Fox News. "I'm also not advocating for keeping the damn thing open and borrowing a million dollars a minute."
The Senate is expected to easily pass the bill if Paul relents. But separate concerns grew in the House as his protest wore on.
A growing number of House Democrats, led by Minority Leader Nancy Pelosi, D-Calif., are threatening to vote against the bill, raising concerns that House leaders may not have the votes to pass the spending bill in that chamber.
"We cannot allow our success in one part of the discussion to diminish our leverage in another," Pelosi said in a letter to Democrats. "Speaker Ryan's refusal to allow a bipartisan process for a DACA proposal demeans the dignity of the House of Representatives. It is also an insult to the American people, who overwhelmingly support the Dreamers."
House Republicans have always expected that they would need some Democrats to help pass the spending bill and the growing revolt has sparked serious anxiety that the spending agreement could fail.
Members of the conservative House Freedom Caucus already announced that their roughly 30 members will vote against the pact.
The two factions are angry about dramatically different issues but their combined frustration could be enough to make sure the bill can't pass.
House Democrats huddled for more than an hour Thursday night to decide how they should vote. Members emerged conflicted.
An official with the White House's Office of Management and Budget told NPR the OMB is currently preparing for a lapse in appropriations funding the government. The official also urged Congress to send the funding bill to the president's desk "without delay."
The deal was announced Wednesday as a bipartisan breakthrough that could free Congress from an endless cycle of spending fights.
The agreement was negotiated by Senate Majority Leader Mitch McConnell, R-Ky., and Senate Minority Leader Chuck Schumer, D-N.Y., to increase military and domestic spending for two years.
Under the pact, the Pentagon would get an additional $80 billion in fiscal year 2018 and an $85 billion in fiscal year 2019, while domestic spending would grow by $63 billion in fiscal year 2018 and $68 billion the following fiscal year.
"No one would suggest it's perfect, but we worked hard to find common ground," McConnell said in a speech announcing the deal.
Schumer echoed the support, saying the agreement would give the federal government certainty after years of bickering.
"This budget deal is a genuine breakthrough," Schumer said, adding the agreement would "break the long cycle of spending crises."
The agreement also has the support of the White House where press secretary Sarah Huckabee Sanders praised the plan to hike military spending.
"This deal achieves our top priority, a much-needed increase in funding for our national defense," Sanders said Wednesday. "The bottom line is that, thanks to President Trump, we can now have the strongest military we have ever had."
This story has been updated.