Michigan has auto dealer licensure requirements, which (as far as I can tell, though I am not a lawyer so you shouldn't believe me) are very similar to those in

Michigan has auto dealer licensure requirements, which (as far as I can tell, though I am not a lawyer so you shouldn't believe me) are very similar to those in New Jersey. Car dealerships do not have more political influence in Michigan than GM does. Also, if it were just a political fight between businesse interests, GM could just go over the states' heads: people frequently buy cars across state lines, so the commerce clause reasoning for a law prohibiting these laws wouldn't even be as tortured as it usually is.