Senate Minority Leader Chuck Schumer (D-N.Y.) speaks Wednesday at the Capitol after President Trump sided with Democrats on adding a three-month extension of the U.S. debt limit and government spending to a hurricane-relief bill over the arguments of fellow Republicans, who pressed for a longer debt extension. (Andrew Harrer/Bloomberg)

Senate Minority Leader Charles E. Schumer could not hide his glee as he approached the microphones Wednesday afternoon.

"Ye of little faith," the New York Democrat chirped to The Washington Post before launching into one of the strangest news briefings of the year. He praised President Trump for siding with him on how to handle the year-end crush of must-pass legislation, including funding the massive recovery effort from hurricane season, and averting a government shutdown and a default on the national debt.

"So it was a really good moment of some bipartisanship and getting things done," Schumer said.

Now that the president has upended Republican plans, Schumer and House Minority Leader Nancy Pelosi (D-Calif.) think they have positioned themselves for a negotiation that will wrap most of the must-pass items into a big Christmas gift in December — the sort of year-end battles that Republicans have routinely lost for more than a decade.

Democrats still must prove, however, that they can actually land those victories. For now, they have secured a seat at the negotiating table.

The big issues include funding for federal agencies and the debt limit, and Democrats will use their votes on those issues as chips to be exchanged for their highest priorities, particularly legislation to codify an Obama-era order granting legal status to more than 800,000 undocumented immigrants brought to the United States by their parents.

President Trump speaks about tax reform at the Andeavor Mandan Refinery in North Dakota Wednesday. (Charlie Neibergall/AP)

Democrats will also demand more money to shore up private health insurance markets, which have been cratering under the uncertainty of the Affordable Care Act's future. In turn, Trump is sure to continue demanding funding for a border wall to back up his 2016 campaign pledge, but key Republicans have signaled that they would instead prefer funds for more border agents and a surge of technology to deter illegal immigration.

For the first time this year, Democrats can envision playing offense, possibly securing victories on immigration and health issues that eluded them in the last years of President Barack Obama's tenure.

These year-end negotiations will take energy away from what is supposed to be the Republican effort to forge a massive tax cut for businesses and families, which many conservatives view as their political absolution for their failure in the health-care debate.

If they're not careful, Republicans could end the year with no major conservative accomplishments to show for their complete control of Washington. This scenario would not only leave Obamacare as the law of the land, but also in better financial standing, and grant long-term legal status to the "dreamers."

Senate Majority Leader Mitch McConnell (R-Ky.), center, joined by, from left, Sen. John Barrasso (R-Wyo.), Sen. John Thune (R-S.D.), and Majority Whip John Cornyn (R-Texas), speaks at the Capitol after President Trump overruled congressional Republicans and his own treasury secretary and cut a deal with Democrats to fund the government and raise the federal borrowing limit for three months, all part of an agreement to speed money to Harvey relief. (J. Scott Applewhite/AP)

That would have been considered a good first year in office for President Hillary Clinton.

And there are only so many times that Senate Majority Leader Mitch McConnell (R-Ky.) will be able to shout "Supreme Court Justice Neil M. Gorsuch" to calm the nerves of rattled conservatives, who expected much more out of the first GOP president and Republican-controlled Congress since 2006.

"The bottom line is we have a lot of issues to come together on. It almost always works out best in a bipartisan way when we can do those issues together," Schumer told reporters.

Republicans staunchly disagree with that view, having repeatedly seen massive year-end negotiations turn into bigger spending deals and few victories for conservatives.

That's why they entered Wednesday's Oval Office meeting with Trump and the bipartisan congressional leadership with a plan of their own: Kick the debt limit until after the November 2018 midterm elections.

That would have decoupled the most volatile issue — a default on the debt threatens global markets — from other issues. It also would provide relief on the issue for Wall Street traders growing jittery over the nuclear standoff with North Korea.

Treasury Secretary Steven Mnuchin, who is supposed to be Trump's point person on the emerging tax proposal, pushed for an 18-month extension of the debt limit, well into 2019.

"The markets dictated it," Mnuchin said, according to a Democrat briefed on the meeting.

Schumer called his bluff. "The markets picked right after the 2018 election? I doubt it," he responded.

McConnell and House Speaker Paul D. Ryan (R-Wis.) agreed with Mnuchin. A little after 10 a.m., less than an hour before the Oval Office meeting, Ryan told reporters the proposal for a short-term boost to debt limit was "ridiculous and disgraceful." He warned that it was "playing politics" with much-needed relief funds for Texas in Harvey's wake and other southern states bracing for Hurricane Irma to make landfall in a few days.

The two leaders know how difficult it is to get Republican votes for raising the debt ceiling, an issue that conservative activists have turned into a purity test and one that primary challengers often use against GOP incumbents. Remove the debt-ceiling issue, until 2019, and the Democrats would have less leverage in the immigration and health-care negotiations.

Instead, Trump undercut his own treasury secretary and his nominal allies on Capitol Hill, siding with the Democratic proposal — perhaps in the belief that it would be an important show of bipartisanship during the hurricane-driven crises.

"We essentially came to a deal, and I think the deal will be very good. We had a very, very cordial and professional meeting," Trump told reporters aboard Air Force One en route to an event in North Dakota.

It followed a brutal August for the relationship between Trump and McConnell, whom the president repeatedly blamed for falling one vote short in the effort to revamp health-care laws. Trump also took to Twitter last month to blame McConnell and Ryan for not settling the debt-limit issue before Congress adjourned for the regular August recess.

Trump also ridiculed Arizona's Republican senators, John McCain and Jeff Flake, during a trip to their state. At his weekly media briefing, McConnell received a question about the intraparty feuding last month and simply ducked the question. "We're in September now," he said.

But McConnell did not hide his irritation with the outcome Wednesday.

"The president agreed with Senator Schumer and Congresswoman Pelosi," he said, setting up the sort of showdown he had been trying to avoid. "That's what I will be offering based on the president's decision."

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