President Donald Trump and congressional GOP leadership will put their governance and deal-making skills to the test in January when a nasty spending battle likely to include some form of major immigration policy change comes to fruition.

“This is a presidency-defining moment,” one GOP congressman told Breitbart News when breaking down the battle that lay ahead over some kind of a legislative replacement for the expiring Barack Obama-era Deferred Action for Childhood Arrivals (DACA) executive amnesty for nearly a million illegal alien youths. The congressman requested anonymity so as to be candid about ongoing negotiations with the White House and congressional leadership.

When the GOP Congress and Trump kicked the spending bill can into January after passing the tax cuts plan, they set up a major leverage point for Democrats on the DACA replacement fight: A January 19 government funding deadline gives Democrats a chance to force Republicans, and Trump, into a corner on amnesty. The battle, already shaping up to be gruesome by all accounts from various House GOP members and staff who have spoken with Breitbart News, will be one for the ages as both political parties—and the various factions in both parties—are expected to leave it all on the field in January to fight for their various priorities.

Several months ago, President Trump announced that he was phasing out the unlawful DACA executive action from his predecessor, former President Barack Obama. That set up an early March deadline whereby the approximately 800,000 illegal alien youths who illegally were bestowed temporary legal status and work permits will eventually lose their documentation after said deadline if Congress—as it normally seems prone to do—does nothing to legislatively replace the program.

Democrats have since been salivating at the opportunity to, from the minority position in both the House and Senate, pick a fight with weak-kneed GOP congressional leadership and with Trump over immigration—an issue that defined President Trump’s victorious 2016 presidential campaign, in which he defeated Democrat Hillary Rodham Clinton in a landslide in the electoral college. Since Trump promised America he would not back any type of amnesty for any illegal aliens—and would instead be tough on immigration and build a wall and enforce America’s laws—Democrats are eager to undermine Trump’s core policy platform by getting him to endorse or back a deal that leads to amnesty.

Republican leaders in Congress, like House Speaker Paul Ryan and Senate Majority Leader Mitch McConnell—both of whom, to varying degrees, back amnesty for illegal aliens—have been likewise looking for a way to force through some kind of legislative DACA deal.

At least two House GOP members told Breitbart News that leadership—including Ryan—has been presenting the DACA deal to membership as something along these lines: In exchange for legislatively granting amnesty to recipients of DACA, Republicans will get funding for President Trump’s border wall, an end to chain migration including language from a bill from Rep. Raul Labrador (R-ID) that would do so, an end to the visa lottery, and E-Verify. That would be accompanied by various other border enforcement and interior enforcement measures on immigration. Most importantly, the deal would take those numbers of DACA recipients who would be granted amnesty legislatively out of the total of allowed legal immigrants per year—offsetting the damage that they do to the U.S. economy.

To bake the deal into a cake, and lock it in and prevent foul play on any side—and to force legislative and congressional action—House members say that leadership is mulling attaching said deal, if it can be reached, into the must-pass spending bill legislation. That way, if it were to be derailed as immigration legislation often is—or it were to be vetoed by President Trump if the final deal is not to his liking—then the resulting failure would have catastrophic consequences, namely a government shutdown.

If a deal were to include all those pieces in the end, some conservatives tell Breitbart News, they may be able to support it. But they are worried that through the negotiating process, pieces that make any kind of wheeling and dealing whatsoever palatable to them will fall by the wayside. One House member tells Breitbart News that GOP leadership, including Ryan and his allies, is pitching this plan to members despite the fact that Democrats have yet to sink their claws into the deal. Democrats are unlikely to want anything in the way of enforcement or immigration reforms attached to their DACA amnesty push, and will fight GOP efforts to ensure that any amnesty comes with changes to other parts of immigration policy like the building of a wall or the end of chain migration.

One House GOP member told Breitbart News that he believes leadership is just saying that the deal includes all of those things for now to numb the GOP base into submission, and keep the wing of the party led by Breitbart News Executive Chairman and former White House chief strategist Stephen K. Bannon lulled into submission. “The lead position is never what you end up with,” this member told Breitbart News on Thursday morning.

For much of President Trump’s first year, the president and the White House have outsourced most of the major legislative workings to Ryan and McConnell. On both healthcare and taxes—the two major issues pushed by the White House in 2017—the White House took a back seat to congressional GOP leaders.

After initially failing on healthcare, the House GOP eventually succeeded and passed a bill repealing and replacing Obamacare. That effort succeeded in no part thanks to Ryan, as he was visiting Hollywood and Europe while the leaders of the moderate Tuesday Group and conservative Freedom Caucus together—outside the purview of leadership—negotiated the final alterations to pass the bill that repeals and replaces Obamacare out of the House. In the Senate, McConnell failed miserably to repeal Obamacare—and has said he plans to give up altogether next year, something for which even Sen. Lindsey Graham (R-SC) has called him out.

On taxes, the White House and Trump administration were slightly more involved—but again, the process was mostly delegated to the congressional leadership and their various committee chairs. That led to a messy, barely-passed, months-late bill finally making it to Trump’s desk just before Christmas—when it was originally on schedule to reach the president before the August recess, had Ryan and McConnell been more competent earlier in the year on both healthcare and taxes.

As such, members in both chambers have little confidence in McConnell or Ryan in this DACA-spending battle. But the process is very far along. Congressional and senior administration officials tell Breitbart News to expect serious action on this front, even though the chance of actual success in the end is unclear.

But most importantly, Republicans on Capitol Hill are looking closely to the White House for signs of leadership from President Trump himself—and from his core inner circle of aides in the White House—because they believe he alone can guide the party through this minefield. Messing with potential amnesty and mixing immigration with a spending bill, especially in an election year, is fraught with potential electoral peril for the GOP. Give away too much, and Republicans’ base could stay home in November. Give away too little, and Democrats could storm the castle riding an anti-Trump big blue wave brewing off the nation’s coast as signified by recent elections in Alabama and Virginia.

That’s not even to mention the issues that senators and congressmen may face in the primaries if they are not careful. Many GOP incumbents on both sides of Capitol Hill already have declared primary challengers, and filing deadlines for candidates to declare against them come up in the month of January and February in many states nationwide—right in the thick of this battle. If someone is considering running against their congressman or senator, that lawmaker they are mulling a challenge against voting for a badly negotiated amnesty grand bargain makes it much easier to justify jumping into a race.

In other words, if the GOP is not careful, it could face impending electoral doom as a result of this DACA war. But that’s not all: Trump’s presidency itself rides on this fight. Trump campaigned vehemently against these kinds of deals on immigration, saying he supports building a wall and deporting all illegal aliens during the 2016 campaign. Going back on that could prove costly for Trump well past 2018 and heading into a re-election campaign in 2020, opening room for a potential primary from the right.

Trump is already likely to face an establishment-backed primary challenger in 2020, as Ohio Gov. John Kasich and outgoing Sen. Jeff Flake (R-AZ)—among others—have hinted at potential runs against him. But, if Trump goes too far towards House Minority Leader Nancy Pelosi and Senate Minority Leader Chuck Schumer on this one, he could find himself surrounded.

Early negotiations on DACA have already fallen through. Pelosi and Schumer originally said after a White House meeting this fall that they had reached a deal with Trump, something the president and White House later denied. Then, the Democrat leaders called off a planned meeting with Trump after the president bashed them on Twitter—but back-channels, sources tell Breitbart News, remain open and flowing as the White House, GOP congressional leaders, and Democratic congressional leaders continually talk about what to do on this front.

“We can’t trust Ryan and McConnell,” a second House GOP member told Breitbart News on Thursday. “We need leadership from the White House here.”

This presents a historic opportunity for Trump to truly step up and take control of the GOP—and the country—if he moves into the driver’s seat here. But he has to take the reins and demand to be in control, because he can. It’s up to him now.