Why did Humphrey win Michigan in 1968?

[King of Kensington]

...when the rest of the East North Central or rust belt states went for Nixon?

[King of Kensington]

http://www.npr.org/sections/money/2015/02/23/385843576/50-years-of-shrinking-union-membership-in-one-map

Funfact: Indiana had more union workers as percentage of the labor force in 1968 but it went for Nixon.

So probably Michigan union workers have a more democratic voting tradition that allowed for him to win.

Fascinating.  Never would have thought Indiana would have been so high. 

Also it may explain Washington State going for Humphrey as well.

[King of Kensington]

Plus Humphrey was from the Midwest (Minnesota) and his message of Economic New Deal Liberalism played fine here.

Don't think that made any difference in Michigan.  Humphrey couldn't even win Wisconsin, the rust belt state most culturally similar to Minnesota.