West Michigan is very conservative, especially up in Dick DeVos land near Grand Rapids. I'm from Oakland County, which usually goes blue in the Presidential election, though by a slim margin.
... So are those the two wealthiest areas in the state?
Oakland County has Bloomfield Hills, one of the wealthiest places in the nation, but also Pontiac. Not sure how the average shapes up.
Pontiac is pretty poor, as I understand. Overall, I think Oakland County is one of the wealthiest counties in the country.