President Trump reminded Republicans on Thursday how easily he could explode his party’s carefully crafted messaging strategy, signaling how difficult it will be to stay unified in the face of Democratic attacks in a challenging midterm election environment.

The House ultimately approved a short-term spending package in an evening vote after Republicans fell in line. The legislation advanced to the Senate, where it faced an uncertain fate because of opposition from both parties; passage requires a supermajority of 60 votes and Democrats are vowing to filibuster.