Senate Democrats are under increasing pressure to block a critical government funding bill this week if they don’t win concessions on protecting Dreamers from deportation, a plan that raises the chances of a partial government shutdown by the weekend.

House and Senate lawmakers are expected to consider a continuing resolution that would fund the government for a few weeks. It would be the fourth “CR” Congress has passed to authorize spending in fiscal 2018 and results from a longstanding disagreement between Democrats and Republicans over long-term funding levels and other matters, including how to handle the Dreamers.