(Bloomberg) -- President Donald Trump and Congress have five days left to agree on must-pass spending legislation, or they risk of leaving Washington for the holidays with a big chunk of the federal government shuttered.

Only one major sticking point remains: Trump’s demand for $5 billion to build a wall at the border with Mexico. Democrats insist on spending no more than $1.37 billion on border fencing, and the president said last week he would be “proud” to shut the government if it will force them to give in to his demands.

Lawmakers have discussed various scenarios but so far they’ve been unable to reach agreement with Trump. With time running out until funding expires on Friday night, the dispute could lead to a prolonged closure, a temporary spending deal, a long-term agreement -- or something in between.

Six of 15 government departments -- representing about three-quarters of discretionary spending -- are funded through Sept. 30, 2019, under legislation passed and signed by Trump earlier this year. A partial shutdown would hit agencies including the Securities and Exchange Commission and the departments of Homeland Security, Treasury, Justice and Interior. More than 420,000 federal employees would work without pay and more than 380,000 workers would be sent home.

Republicans and Democrats agree on virtually all other issues to keep nine government departments and various independent agencies from closing on Saturday after funding runs out. The departments of Defense, Veterans Affairs, Energy, and Health and Human Services, among others, are funded and would operate normally.

Second-ranking Senate Republican John Cornyn of Texas said last week he didn’t see any clear path to a resolution. “Put me down as puzzled,” he said. “I don’t see the end game."

Here are some scenarios for how the shutdown fight may play out:

Prolonged Government Shutdown

Many lawmakers and congressional aides see a shutdown lasting at least into January, when Democrats will become the House majority and begin passing spending bills to pressure the Republican-controlled Senate and Trump to reopen the government.

“It looks like we’re headed to a shutdown. But who knows? We’ve got time,” Senate Appropriations Chairman Richard Shelby, an Alabama Republican, told reporters at the end of last week.

Because a shutdown would be more limited than previous closures in 2013 and the mid-1990s, the public would see fewer effects and there may be less pressure to end it quickly.

"The president drew a pretty clear line in the sand and said he won’t compromise with anybody," said longtime Republican congressional aide Jim Dyer, now a senior adviser at the lobbying firm of Baker Donelson. "You’re at the point where you are looking around for somebody to talk to and that means we are looking at a shutdown."

Brief Shutdown

Earlier this year, Senate Minority Leader Chuck Schumer of New York caused a weekend shutdown by pushing Trump to agree to protect young undocumented immigrants from deportation. As public pressure mounted, Schumer backed down and employees returned to work by Monday. To reach a quick resolution, Congress and the president would either agree to a deal, or one side would back down after the shutdown starts.

Split the Funding

Shelby floated a compromise this month in which Trump’s $5 billion would be split over two years. Trump privately said he was open to the idea, but Schumer rejected it. As a shutdown deadline approaches, this possibility could look more appealing.

More Money But No Wall

Senate Democrats earlier this year supported $1.6 billion for border fencing rather than $1.3 billion. That could be where the final deal ends up, giving more money for border security while preventing Trump from getting the concrete wall he promised his supporters. This could allow Democrats to claim victory as well.

Stopgap Spending Bill Into January

All sides could agree to extend current funding until sometime next month and resume the fight over the wall then. House Republicans, in the waning days of their majority, are having trouble getting their own departing members to show up and fight for the wall, and Trump plans to spend 16 days at his Florida resort over the holidays.

Waiting until January would make the wall dispute a more direct confrontation between Trump and likely House Speaker Nancy Pelosi of California, while also stepping on her planned message of cooperation with the president in the new year.

Stopgap Spending Into the Spring

Lawmakers could keep current spending levels into March or later. The federal debt ceiling comes back into effect March 1 and will require another negotiation, so both parties may decide it makes sense to combine the issues. Congress will also try to strike a new deal on budget caps to prevent automatic spending cuts now slated for 2020.

Spending Bill Until June

Earlier this year, Schumer and Trump attempted to craft a deal on immigration that would have provided $25 billion the wall in exchange for protection for young immigrants. That was scuttled after conservatives insisted on changes to legal immigration, and court challenges halted attempts to deport the immigrants. Pushing the border wall fight into June, when the Supreme Court may decide to clear the way for deportations, could create pressure for another grand bargain.

Full-Year Stopgap Spending

Schumer and Pelosi offered this option to Trump during a heated Oval Office meeting last week. All unfunded agencies would stay at current levels through September with some negotiated exceptions, such as adding disaster aid for hurricane and wildfire relief. Trump has resisted this option because it would only provide $1.37 billion for fencing at three sections of the border. New language could be inserted to allow fencing in additional areas.

Six Full Spending Bills

This is the main offer from Democrats to Trump. The departments of Agriculture, Interior, Transportation, Housing and Urban Development, Treasury, State, Commerce and Justice and related agencies would get new spending amounts through September.

Grand Bargain Re-Emerges

Trump could ignore the pressure from conservatives and cut a deal with Schumer for wall money in exchange for protecting young illegal immigrants. Pelosi, who previously opposed such a plan, could negotiate sweeteners for her progressive wing as part of this deal. So far there is no sign of this deal coming together.

Trump Wins

The name of the game in shutdown fights is avoiding blame. By saying on national television that he would accept blame for any shutdown, Trump has put himself in a tough position to get $5 billion for a concrete wall. Pelosi, who needs 218 Democrats to support her in a Jan. 3 election for House speaker, is in no mood to give in. That makes this the least likely scenario. Slightly less implausible: Democrats allowing a small section of wall to be built.

To contact the reporter on this story: Erik Wasson in Washington at ewasson@bloomberg.net

To contact the editors responsible for this story: Joe Sobczyk at jsobczyk@bloomberg.net, Laurie Asséo, Justin Blum

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