Devos and Johnson

The gender-balancing tradition at the top of the ticket goes on.
Democratic Gov. Jennifer Granholm, of course, has a male lieutenant governor. Mr. Devos, who certainly can't be considered a mushy liberal, announces a female nominee.
Republican John Engler had a female No. 2 for two of his three terms. Democrat Jim Blanchard, elected a generation ago, had a female lieutenant governor for both his terms.
The last male Michigan governor to have an all-male cast of lieutenant governors (he had three) was William Milliken.
Is it affirmative action? Or is it simply facing political reality in the heartland?