Grand Rapids, Ionia and Muskegon became home to those of Mexican heritage who worked for the railroads. Throughout the state, there are handfuls of Mexican-American communities whose residents are the descendants of those braceros who worked in agriculture until they could earn enough money to set out on their own.
There's much more cultural geography in the article, but I thought the braceros reference most interesting. Braceros were guest workers and they weren't supposed to settle in the United States. They are the equivalent of the German Gasterbeiters, mainly Turks who came to Germany in droves during the post-WWII economic boom. During lean times, tensions arise between natives and migrant labor.
Cinco de Mayo is a big deal where I live (Front Range of Colorado). The main festival was on Saturday. There was a large immigrant protest parade. It's a touchy subject in a community with a long history of foreign born labor working the fields (e.g. Japanese in the sugar beet industry). I've seen quite a bit of American flag waving today. I haven't noticed any word about a similar backlash in Michigan. With unemployment so high and all the recent news coming out of Arizona, I would imagine that there is some latent anger seething beneath the surface. Iowa might be a Midwestern state to track given the recent immigration there.