When environmental groups asked the Illinois Pollution Control Board to impose a California-style mandate for electric cars and trucks, the primary legal pushback didn’t come from traditional foes such as ExxonMobil. It came from within the inner sanctum of the Illinois Democratic Party. In a counterstrike, Local 150 of the International Union of Operating Engineers filed a motion in August to dismiss the electric vehicle petition. Environmentalists should make their case in the legislature instead, the union said.