Updated at 2:15 p.m. ET

Senate Minority Leader Chuck Schumer, D-N.Y., headed to the White House Friday afternoon following an invitation from President Trump to discuss a path forward to avoid a partial government shutdown.

The meeting began less than 12 hours before the midnight deadline for Congress to pass a new spending bill. Democrats and Republicans remain deadlocked without a path forward, even as both sides face potentially dramatic political fallout if a shutdown does occur.

Republicans stepped up their attacks on Democrats in the hours leading up to the White House meeting, blaming them for forcing the standoff. Senate Majority Leader Mitch McConnell, R-Ky., accused Democrats of using immigration as a bargaining chip in the fight.

"The Senate is now just hours away from an entirely avoidable government shutdown," McConnell said Friday morning on the Senate floor. "The craziness of this seems to be dawning on my friend the Democratic leader."

Senate Democrats insist they will not vote for a stopgap measure without an agreement for long-term increases in military and domestic spending and a pathway to citizenship for roughly 700,000 immigrants. Those are individuals who are in the country illegally after being brought here as children, and are enrolled in the Deferred Action for Childhood Arrivals program established by the Obama administration. Those protections from deportation are set to begin expiring in March after the Trump administration announced it was rescinding DACA last year.

"Government Funding Bill past last night in the House of Representatives. Now Democrats are needed if it is to pass in the Senate - but they want illegal immigration and weak borders. Shutdown coming? We need more Republican victories in 2018!" Trump tweeted at 7:04 a.m. ET.

Democrats launched into a last-minute flurry of talks late Thursday following a House vote to approve a short-term spending bill to keep the government open until Feb. 16 and fund the popular Children's Health Insurance Program, or CHIP, for six years. Schumer and Senate Majority Leader Mitch McConnell, R-Ky., say they want to avoid a shutdown, but both leaders have become increasingly insistent that they are unwilling to compromise on their demands.

McConnell and other Republicans say they have more than a month to agree to an immigration package before the Deferred Action for Childhood Arrivals program, or DACA, is set to expire. They are calling on Democrats to back the short-term bill in order to give them more time to negotiate.

Republicans are already dubbing it the " Schumer Shutdown" after Senate Minority Leader Chuck Schumer, D-N.Y., who has warned Republicans that they will not have enough Democratic votes to break the 60-vote filibuster threshold.

It is unlikely that Senate Majority Leader Mitch McConnell, R-Ky., even has a simple majority of Republicans to support a House-passed stopgap measure to keep the government running until Feb. 16. Republican Sens. Lindsey Graham of South Carolina and Jeff Flake of Arizona have indicated they will oppose it.

"I am not going to support continuing this fiasco for 30 more days by voting for a continuing resolution," Graham said Thursday. "It's time Congress stop the cycle of dysfunction, grow up and act consistent with the values of a great nation."

The Senate convened Friday morning, but lawmakers and aides said there is no consensus on how to head off the impending midnight partial government shutdown.

Sen. Chris Van Hollen, D-Md., who runs Senate Democrats' 2018 campaign operation, told NPR's Morning Edition that Democrats would support a stopgap measure for three to four days to keep the government running and give negotiators more time to clinch deals in stalled immigration and budget talks.

"I'm not voting for a government shutdown. I'm voting to get an agreement to move forward," Van Hollen said. "Let's stay in. Let's get it done." The White House and Senate GOP leaders have not yet indicated whether they would accept that offer.

Van Hollen also said Trump, not the Democrats, will shoulder the blame if a shutdown occurs. "If the president of the United States, whether by design or incompetence is going to shut down the government, that is a big problem," Van Hollen said. "I hope he will show some leadership; he says he's the great negotiator."

New data seems to agree. A Washington Post-ABC News poll out Friday found that 48 percent of Americans would blame Trump and Republicans for a shutdown, compared to 28 percent who would blame Democrats. The rest of the participants either blamed both equally, or had no opinion.

Shutdowns are usually the product of divided government. A midnight shutdown would be the first time one occurred when the same party controlled both chambers of Congress and the White House.

Still, the Trump White House is working hard to shift blame back to the Democrats.

"There is no way you could lay this at the feet of the President of the United States," said Mick Mulvaney, the director of the Office of Management and Budget in a press conference on Friday.

"The reality is Republicans are united in keeping the government open. Democrats are united in trying to shut it down," White House Legislative Affairs Director Marc Short told NPR's Morning Edition.

Short downplayed the merits of an even shorter stopgap, arguing that negotiators need more time to reach an immigration deal to determine the fate of the hundreds of thousands of people in the Deferred Action for Childhood Arrivals immigration program. Trump has ordered the Obama-era DACA program, which protects immigrants brought to the U.S. illegally when they were children, to expire on March 5. "I think we're making progress on DACA, but I think it's unrealistic to think there's going to be a solution in the next five days," Short said.

Republicans have also sought to call attention to what they see as hypocrisy from the Democratic leadership, who loudly criticized Republicans in 2013 when the government last shut down, over Affordable Care Act disagreements.

The House passed the four-week stopgap on Thursday, 230-197, with just six Democrats voting with Republicans. The measure includes a six-year renewal of the popular Children's Health Insurance Program and further delays of certain taxes under the Affordable Care Act, also known as Obamacare.

There is ostensibly Democratic support for all of those provisions, but the vast majority of Democrats oppose the stopgap because of the ongoing inability to reach a bipartisan immigration deal. Democrats are also withholding support for a longer-term spending deal until an immigration deal is clinched.

"This vote should be a no-brainer," McConnell said Friday morning on the Senate floor. "And it would be, except the Democratic leader has convinced his members to filibuster any funding bill that doesn't include legislation they are demanding for people who came into the United States illegally."

The president has been an erratic negotiator in recent days, throwing already-contentious talks into disarray. After initially suggesting he would support any bipartisan proposal lawmakers could come up with, Trump rejected a proposal authored by Graham, a Republican, and Senate Minority Whip Dick Durbin, D-Ill., at the advice of more conservative lawmakers and his own top White House aides.

Trump was also seemingly at odds with his own chief of staff, John Kelly, over the president's continued support for building a physical barrier along the U.S.-Mexico border. Kelly told Fox News that Trump was "flexible" on the wall, to which Trump later tweeted: "The Wall is the Wall, it has never changed or evolved from the first day I conceived of it."

Trump further complicated budget negotiations on Thursday with a series of tweets that suggested he opposed the House stopgap bill. The White House put out a statement later that he did support it, and the president ultimately helped win over reluctant House conservatives to vote for the bill.

Most Americans would not feel the effects of a partial government shutdown. However, hundreds of thousands of federal workers would face furloughs.

"The military would still go to work, they will not get paid. The border will still be patrolled, they will not get paid," said Mulvaney, the director of the Office of Management and Budget. "Folks will still be fighting the fires out west, they will not get paid. Parks will be open, people won't get paid."

All national security and military personnel deemed "essential" would continue to report to work, but they wouldn't get paid. That includes active-duty U.S. troops, unless Congress passes separate legislation to make sure their paychecks go out. Lawmakers, however, face no such threat. Members of Congress continue to get paid in a government shutdown.

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