WASHINGTON — Democrats who voted on a spending bill this week to keep government open are facing an angry backlash from their own party for not demanding a permanent solution for thousands of undocumented immigrants brought to the U.S. as children.

Immigration advocates in and out of Congress are railing against those who voted for the stopgap bill late Thursday despite promises from Democratic leaders that they would force action on the issue by the end of the year. Even before the Senate vote, a group of House Democrats burst into the office of Sen. Charles Schumer, D-N.Y., the Senate minority leader, demanding an explanation. Protesters shouting “shame on Kaine!” briefly occupied the office of Sen. Tim Kaine, D-Va., who said he voted for the measure to prevent a partial government shutdown and protect federal employees.

“Every single Democrat who voted for the continuing resolution just voted to deport Dreamers and leave kids without access to health insurance,” said Murshed Zaheed, the political director of the California-based progressive group CREDO. “Quite frankly, it’s a pathetic way for the Democratic Party’s leadership to close out a year in which millions of Americans fought back and resisted the Trump regime’s racist, xenophobic and dangerous agenda.”

The internal party drama is sure to ratchet up the pressure on Schumer and House Minority Leader Nancy Pelosi, D-Calif., to pass the so-called Dream Act in January, when the latest stopgap spending bill is due to expire. It also threatens unity – and perhaps divisive primary challenges – at a time when Democrats are looking ahead to the 2018 midterms with new optimism that they have a chance to take control of both chambers.

The current push for immigration legislation erupted in September, after President Trump vowed to end a program known as Deferred Action for Childhood Arrivals, or DACA, instituted by former President Obama via executive action and allowing some immigrants brought into the country as children to stay legally.

At the time, Pelosi and Schumer pledged to enshrine the protections of DACA into law quickly, and advocates have kept the pressure up to ensure they do.