Last week, Congress authorized a bill securing $4.6 billion in funding for “humanitarian assistance and security” at the U.S.-Mexico border. On Monday, President Donald Trump signed the bill into law. It passed with strong bipartisan support, and yet the measure has proven divisive and demoralizing among Congressional Democrats, who wanted stronger protections for migrants detained at the border. The bill was initially sponsored by Democratic representative Nita Lowey to alleviate the judicial backlog migrants face, improve conditions at the detention facilities where they are being held, and limit the Trump administration’s ability to redirect the “humanitarian” funding for more ICE raids and deportations, but it was watered down by the Republican-led Senate. “In order to get resources to the children fastest, we will reluctantly pass the Senate bill,” House Speaker Nancy Pelosi said. Pelosi reportedly blames Senate Democrats, led by Minority Leader Chuck Schumer, for aligning with the Republican majority. “Chuck Schumer fucked us,” a senior Democratic staffer told Vanity Fair. Congressional Democrats seem all but powerless despite regaining control of the House after the midterm elections.

Under both Barack Obama’s and Trump’s administrations, Congress has repeatedly deadlocked over immigration reform efforts, and thus ceded policy to the presidency; Obama and Trump legislated their respective immigration priorities largely through executive order. Of course, most of the Democratic presidential candidates, if elected, have promised to wield their executive authority to reverse Trump’s immigration restrictions. But executive orders can be no match against an obstructionist Congress. Even if the Democrats defeat Trump in 2020, as long as the Republicans control the Senate, Majority Leader Mitch McConnell would see to it that there were few substantive legislative differences between a potential Biden presidency and a socialist Sanders presidency. “Short of a Democratic majority in the Senate,” Massachusetts Senator and presidential hopeful Elizabeth Warren said at last week’s first Democratic debates, “you better understand the fight still goes on. It starts in the White House and it means that everybody we energize in 2020 stays on the front lines come January 2021.” Colorado Senator Michael Bennet offered a far more realistic and dismal assessment during the second night of debates. “Gridlock will not magically disappear as long as Mitch McConnell is there,” Bennet said. Bennet implored Democrats to fight Republican efforts to gerrymander Congressional districts and win back the Senate. NBC’s moderators moved on.

The debates in Miami were held across two nights to accommodate the unconscionably large Democratic presidential field. The roster comprises a couple of dozen political candidates, mostly senators, and a few rising stars in the party who have inserted themselves into the campaign season despite long odds of winning and, arguably, better uses of their time and talents: The wunderkind from El Paso, Beto O’Rourke, who nearly defeated Texas Senator Ted Cruz in the midterms last November, declined to challenge John Cornyn for his Senate seat in 2020 so he could run for president instead. For Democrats, Trump’s unpopularity turns the presidential election into an incomparable opportunity: Who wouldn’t want to challenge the least popular U.S. president to ever run for re-election?

In the five months since Warren announced her candidacy and unofficially kicked off election season, Democrats have come to define their post-Trump ambitions for governance in purely presidential terms. First-term Democratic representatives Alexandria Ocasio-Cortez, Ilhan Omar, Ayanna Pressley, and Rashida Tlaib lead a left-wing insurgency in the House, expanding Sanders’s movement into the legislative realm. Generally, however, Sanders hasn’t radicalized Congressional Democrats as thoroughly as he has his fellow presidential candidates.

Sanders has spent the past few years billing his presidential aspirations as one part in a larger socialist project. He has a coherent legislative outlook, a national network, and ideological successors who have been elected to office. The other Democratic contenders struggle to account for Congress in their post-Trump political vision. Democrats have spent the past decade learning about the perils of divided government and legislative brinkmanship, but there’s little optimistic talk among them about taking back the Senate any time soon. If Sanders wins the nomination, the party may well pit the country’s first socialist president against a Republican-led Senate; further complicating his governance will be the moderate Democrats who dominate Pelosi and Schumer’s ranks. Congressional Democrats at the current moment are too weak to impeach Trump. If the president loses his re-election bid, they may prove too weak to realize their party’s post-Trump impulses—from the “resistance” to the socialist movement—as a dominant governing agenda. Trump may lose, but Pelosi and Schumer will remain. So, too, will McConnell.