Michigan vs. Ohio

My answer was mostly based on the higher population in Ohio, and the lack of population density in Michigan. In Ohio there are four big cities (Columbus, Cincianatti, Cleveland, and Toledo) within the top 100 cities for US population, and they're all well spread out. Michigan's largest city, and only city that rivals any of Ohio's large cities for population is Detroit, and it's right near the border. A full-force invasion would be disastrous for Michigan either way, so all Michigan could do is sit back and hope they aren't invaded by Ohio. Alternatively, if they did invade they could probably take a good portion of the area around Lake Eerie, but they'd instantly fall to any offensive attack from Ohio.

Just my thought on the matter. Ohio would rip Michigan to pieces!

I do have family in Ohio, if you think that affects my answer, but some of them moved to the Detroit suburbs as well.