Unable to bridge the partisan divide on immigration, federal spending levels and more, Republicans and Democrats in the Congress were on the verge of letting funding for the government lapse at midnight on Friday night, as members of both parties eagerly pointed the finger of blame at each other for the spending impasse, which could trigger the first federal shutdown in over four years.

"That would be a mistake," said Sen. Rob Portman (R-OH). "Government shutdowns do not make sense."

That Republican argument carried the day in the House, as lawmakers voted mainly along party lines Thursday evening in favor of a four week temporary funding plan - but once the bill reached the Senate floor, leaders quickly sent Senators home for the night, unable to agree on how best to proceed.

"They're prepared to shut down the government over the issue of illegal immigration," Senate Majority Leader Mitch McConnell declared of Democrats, as McConnell said there was no reason to rush on solving problems with DACA and Dreamers, as GOP leaders struggled to get a majority of Senators to vote for the House-passed bill.

Meanwhile, Democrats complained that immigration talks have been slow walked by Republicans and the White House, and that it was time to force a solution on immigration, overall budget limits and more.

"We should be united in trying to come to a solution, not just kick the can down the road," said Senate Democratic Leader Charles Schumer.

If Congress is unable to reach a spending agreement by midnight, then many government functions would start to wind down over the weekend.

In the House, Republicans said now was the time for more negotiations, not a spending impasse which would close many government operations.

"We've kept the government open," said Rep. Tom Cole (R-OK). "The right thing for the Senate to do would be to vote yes, and continue to negotiate."

"I now just implore the Senate, do your job," said Rep. Doug Collins (R-GA).

As Senators gathered on the floor late Thursday, a number of illegal immigrant "Dreamers" were seated in the galleries, watching the debate below.

"Look at the people who have gathered here late this night, who are following every word that we are debating," said Sen. Dick Durbin (D-IL).

"Why are they here if there's no urgency?" added Durbin, who is a leading negotiator for Democrats on DACA and immigration issues.

But while Durbin and other Democrats called for action on a bipartisan agreement on Senators from both parties related to DACA, their plan had still not been put into legislative language.

GOP Senators pointed out that lack of a bill in making the case that no deal was likely over the weekend on immigration, and again saying that the deadline was not until March.

"This institution regrettably needs to be forced into action," said Rep. Carlos Curbelo (R-FL), who broke ranks with his party's leadership to vote against a stopgap budget, demanding immediate action on DACA.

"We don't have to wait until March, it would be cruel to wait until March," Curbelo told reporters after the House had voted.

At first, President Donald Trump was still planning to leave town on Friday afternoon for his Mar-a-Lago retreat in Palm Beach, Florida - but White House officials indicated he would delay that, waiting to see what happens in the Congress on the shutdown.

Also on Mr. Trump's Friday schedule was an address to thousands rallying for the March for Life, and a meeting with his national security team in the White House Situation Room.

Democrats only saw one thing - Air Force One leaving town.

"Trump going to Mar-a-Lago while government shutdown looms is most irresponsible, self absorbed, dereliction of duty ever by a President," tweeted Rep. Steve Cohen (D-TN).

But even as both sides traded barbs, there was a lot of frustration among Republicans over the budget process, which has become stuck in neutral on a regular basis.

"It is absolutely ridiculous that we are sitting here today, having not funded the government permanently for the balance of this year," said Sen. David Perdue (R-GA).

If the federal government does shut down this weekend, it would be the first spending impasse since 2013, when Republicans blocked action on funding bills for 16 days, protesting the implementation of the Obama health law.