Congress on Monday passed a spending bill that ended a three-day shutdown and gave lawmakers three weeks to find a way forward on immigration, but reaching a deal will either be difficult or impossible, and there's a real risk lawmakers get into another shutdown fight in early February.

The goal is to find an agreement that protects the Dreamers, which Democrats want, in return for border wall funding and other immigration policy changes sought by Republicans.

But obstacles are everywhere.

First, Senate Majority Leader Mitch McConnell, R-Ky., has not been clear on what immigration measure he would allow on the Senate floor. Minority Leader Chuck Schumer, D-N.Y., said if there's no broad agreement, the Senate would vote only on a bill to codify the Deferred Action for Childhood Arrivals program, which President Trump has said he would rescind by early March.

But even if the Senate can find a way forward, that deal will likely hit a brick wall in the House, where anything other than a conservative pro-border security proposal faces significant GOP opposition.

If the deal stalls in the House, or never takes flight in the Senate, Democrats could again threaten to block the next spending bill that's needed after Feb. 8.

On the Senate side, Minority Whip Dick Durbin, D-Ill., and other Democrats want to call up a bill co-authored by Sen. Jeff Flake, R-Ariz., that would protect Dreamers from deportation in exchange for moderate border security spending and no alternations to chain migration, the visa lottery system, or major increases in interior immigration enforcement.

Democrats face increasing pressure from their progressive base, who reacted in anger Monday when Democrats agreed to back the Feb. 8 deal even though it did not include a provision to protect the Dreamers from deportation.

Durbin and Flake will push McConnell to take up their measure. But many Republicans are known to oppose that, and McConnell in particular has said the Senate needs to be mindful of what Trump is willing to sign into law.

On the House side, Speaker Paul Ryan, R-Wis., is offering no promises beyond trying to negotiate a deal with Democrats.

“What we're saying is, open the government, and then we'll get back to these negotiations,” Ryan said on Fox early Monday.

House Republican leaders know if they bring the Durbin immigration bill to the floor, it will cost them the support of a major segment of their conference and perhaps their leadership positions.

A significant group of GOP lawmakers want stronger border security and more significant changes to immigration policy that are included in a bill authored by House Judiciary Committee Chairman Bob Goodlatte, R-Va.

“If they want something that is going to pass the House of Representatives, with a majority of the Republican conference, they need to start putting the Goodlatte bill in play,” said Rep. Raul Labrador, R-Idaho, who co-authored the Goodlatte measure. “That’s the only way we are going to get to Republicans voting on something in the House of Representatives.”

In addition to Durbin’s bipartisan group, another set of bipartisan lawmakers and Trump administration officials have been negotiating for weeks in the Capitol on a bill that would protect Dreamers but require a significant boost in border security, as well as changes to chain migration and the visa lottery system, among other provisions.

Democrats involved in those talks say they are going nowhere. But Republicans have been more optimistic and say they are progressing toward a deal.

Among the participants is Rep. Kevin McCarthy, R-Calif., the House majority leader and No. 2 Republican who has his eye on the top leadership job if Ryan ever steps aside.

House conservatives are watching McCarthy closely and expect him to hold the line on an immigration reform bill that can win the backing of House conservatives by incorporating the provisions in the Goodlatte bill.

“McCarthy understands his political future is at stake here,” Labrador said.

But the two-track effort so far seems to be setting up the likelihood of more conflict that could lead to another spending impasse. Without a deal on immigration by Feb. 8, Democrats have suggested they’ll oppose a new spending deal and thus create another shutdown crisis.

Meanwhile, Republicans appear to be ready to have the fight all over again after the broad consensus that the GOP won this week's shutdown fight with Democrats. McConnell said Monday that the Democrats lost the three-day shutdown battle and suggested that the tactic won’t work next month, either.

“I think if we've learned anything during this process, it’s that a strategy to shut down the government over the issue of illegal immigration, is something the American people didn't understand and would not have understood in the future,” McConnell said.