House and Senate Democrats will have to resolve a bitter internal battle over spending in order to pass the two-part social welfare and infrastructure spending measure that lawmakers hope will become the party’s signature achievement ahead of the 2022 midterm elections.

Democratic leaders have scheduled only a handful of legislative workdays in September despite a seemingly impossible to-do list: pass a $3.5 trillion social welfare spending package along with a separate $1.2 trillion infrastructure bill while also ensuring the government remains operating by clearing a stopgap funding bill by Sept. 30.