The spending legislation passed 71-28, with wide bipartisan support. The bill would reopen the government while showering hundreds of billions of dollars on defense and domestic priorities, speeding disaster aid to hurricane-hit regions, and lifting the federal borrowing limit for a year. But first it must pass the House, where opposition from the left and the right made the outcome uncertain.
House votes were expected later Friday morning.
The shutdown was so unanticipated that the Office of Management and Budget didn't tell federal agencies to prepare for it until Thursday evening. But depending on House action the closure could end up being brief and having little impact on federal workers and the public.
Still, Congress' inability to keep the world's largest economy running pointed to acute legislative dysfunction that has paralyzed the Capitol and forced the government to operate on one short-term spending bill after another since the fiscal year began Oct. 1. The budget deal headed for passage Friday was meant to break that cycle of budget dysfunction - before it, too, ran into dysfunction.
The partial shutdown began just after midnight Friday morning as the government ran out of money when the latest short-term spending bill expired without Congress passing a new one.
Last month, the government shut down for three days in a dispute over undocumented immigrants brought to the country as kids, reopening when Senate Democrats accepted assurances from Senate Majority Leader Mitch McConnell, R-Ky., that he would hold a floor debate on immigration this month.
The latest congressional breakdown came amid dispute over the spending deal, which earlier in the week had appeared primed for easy passage as McConnell and Minority Leader Charles Schumer, D-N.Y., unveiled it jointly on the Senate floor with a bipartisan flourish and mutal praise.
But it began to run into trouble Thursday, as House conservatives rebelled over excessive deficit spending and House liberals fumed that this bill, too, failed to protect "dreamers" who face losing deportation protections under the Trump administration.
Then, as an expected vote approached in the Senate, Paul began to throw up roadblocks, demanding a vote on his amendment that would demonstrate how the two-year budget deal breaks past pledges to rein in federal spending.
GOP leaders refused to allow him to offer the amendment, arguing that if Paul got an amendment vote, many other senators might want one, too. Paul, in turn, refused to allow the vote to go forward, making use of Senate rules that allow individual senators to slow down proceedings that require the consent of all.
"I can't in all good honesty, in all good faith, just look the other way because my party is now complicit in the deficits," Paul said on the Senate floor as evening pushed into night.
Paul objected after a visibly irritated McConnell tried to move to a vote. Then Paul launched into a lengthy floor speech deriding bipartisan complicity on deficit spending while the country goes "on and on and on, finding new wars to fight that make no sense." The senator direly predicted a "day of reckoning," possibly in the form of the collapse of the stock market.
As the hours ticked on, Paul repeatedly refused to consent to allowing the vote to happen, as lawmakers and aides of both parties grew increasingly annoyed at him. Sen. John Cornyn, R-Texas, leaving the floor after an unsuccessful attempt to curtail Paul's standoff, called the gambit "grossly irresponsible" and said that leaders would not entertain his demand for a vote.
"Why reward bad behavior?" Cornyn said.
Senate leaders remained confident all along that the spending deal would pass easily in the end, as it did. But without an agreement among all senators on timing, the voting was delayed until 1 a.m., when all time allotted for debate expired. And by then, the government had been shut down for an hour.
Senators of both parties were left fuming, with most of their ire directed toward Paul.
"He has mastered the art of ticking off his colleagues," said Sen. Christopher Coons, D-Del.
"It's a colossal waste of everybody's time," said Sen. John Thune, R-S.D. Of Paul, Thune said, "He never gets a result."
Paul himself made no apologies as he delivered one floor speech after another, casting himself as a lone defender of fiscal austerity, despite having voted in December for a tax bill that added at least $1 trillion to the debt.
Meanwhile even bigger problems appeared to be surfacing in the House, where liberals led by Minority Leader Nancy Pelosi, D-Calif., were incensed that the plight of young undocumented immigrants who face the threat of deportation was not addressed in the spending bill.
Pelosi planned to vote against the bill. And despite initially suggesting that she would not be urging fellow Democrats to follow her lead, she increasingly appeared to be doing exactly that.
At a closed-door evening meeting of House Democrats, Pelosi told lawmakers: "We have a moment. They don't have the votes. All of us should use our leverage. This is what we believe in," according to one House Democrat in the room, who spoke on the condition of anonymity to disclose the private conversation.
Pelosi is under intense pressure from immigration activists and liberals in her caucus to take a stand for the "dreamers" - undocumented immigrants brought to the country as children who face losing work permits granted by President Barack Obama under the Deferred Action for Childhood Arrivals program (DACA) but rescinded by President Donald Trump.
Supporters of these immigrants have watched in growing outrage as Democrats have failed repeatedly to achieve results for the cause. They want to see Democrats stand strong, even after last month's shutdown failed to achieve anything more than a commitment from McConnell to debate the issue on the Senate floor.
But many House Democrats were skittish over another shutdown, especially with Senate Democrats largely on board with the spending deal.
Several House Democrats emerged from their caucus meeting resolved to hold the line against any deal that did not address the party's immigration concerns.
"I think there's a very strong sentiment that this is a moment that we can't let pass," Rep. Daniel Kildee, D-Mich., said. "We've allowed these moments to pass in the past. This is a moment we can't let pass without doing everything we can to move forward on DACA."
Others were unconvinced.
Rep. John Yarmuth, D-Ky., the top Democrat on the House Budget Committee and a supporter of the deal, said the outcome may well depend on forces out of the House Democrats' control, such as how many House Republicans support it.
"If Republicans had 70 votes and needed 140 from us, then there's no pressure on us, because then it's their fault," Yarmuth said. "But if they have 170 and we can't put up 40 to support a bipartisan bill coming from the Senate, then we get blamed for a shutdown."
House conservatives were also balking, objecting to the enormous increase in federal spending, most of which would be piled onto the deficit with minimal attempts to offset it.
Earlier Thursday, House Speaker Paul Ryan, R-Wis., expressed confidence that the bill, which delivers a military funding boost sought by the GOP alongside increases in domestic spending favored by Democrats, would pass. "There is widespread agreement in both parties that we have cut the military too much, that our service members are suffering as a result, and that we need to do better," he said.
If the bill does pass in the end, its impact would range far beyond the military- renewing several large health-care programs, suspending the national debt limit for a year and extending billions of dollars of expiring business tax breaks. The cost of those provisions exceeds $560 billion, though lawmakers included some revenue-raising offsets, such as increases in customs fees and a sell-off from the Strategic Petroleum Reserve.
In comparison, the 2009 fiscal stimulus bill passed at the bottom of a global recession under Obama was estimated to cost $787 billion over 10 years. Republicans were nearly unanimous in opposing that measure in their clamor for fiscal restraint in the face of growing deficits - demands largely drowned out now in the Trump era.
This spending bill, proposed amid an economic boom, could be the last major piece of legislation passed before November's midterm elections, barring a breakthrough on the thorny immigration debate.
Under the deal, existing spending limits would be raised by a combined $296 billion through 2019. The caps were put in place in 2011 after a fiscal showdown between Obama and GOP congressional leaders, who demanded spending austerity.
The agreement includes an additional $160 billion in uncapped funding for overseas military and State Department operations, continuing a costly line item that dates back to the immediate response to the 2001 terrorist attacks. And about $90 billion more would be spent on disaster aid for victims of recent hurricanes and wildfires. Tax provisions would add another $17 billion to the cost of the bill.
The bill also includes a provision suspending the federal debt limit until March 1 of next year - after November's midterm elections.
(Except for the headline, this story has not been edited by NDTV staff and is published from a syndicated feed.)