Washington (CNN) As a massive bipartisan budget deal moved towards a vote Thursday, temperatures were rising on the left, where Democrats were fuming that -- once again -- immigration was being left behind.

"Anyone who votes for the Senate budget deal is colluding with this President and this administration to deport Dreamers. It is as simple as that," said Illinois Rep. Luis Gutierrez, a longtime Democratic advocate of immigration reform. Pro-immigration advocacy groups were sending similar messages to Democratic offices as well.

Democrats on the left, especially members of the Congressional Hispanic Caucus, were frustrated to see a budget deal negotiated that resolved virtually every Democratic priority except a resolution for the Deferred Action for Childhood Arrivals program, a policy that protected young undocumented immigrants who came to the US as children that President Donald Trump decided to terminate in September.

The Senate is expected to pass the bill Thursday and send it to the House attached to a continuing resolution to fund the government into March. Government funding expires Thursday at midnight.

The pushback was strong enough that House Minority Leader Nancy Pelosi, who was involved in negotiating the compromise, was so moved by the frustration when she presented the deal to her caucus that she took the House floor for a record-breaking eight hours straight on Wednesday, reading stories of DACA recipients.

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