Here’s another look at the polarization question drawing on the data from the Hotline/Diageo poll (PDF). Here, I suppose, we can see a sense in which Hillary Clinton is “polarizing” — she has relatively few mild detractors. Those who don’t approve of her tend to strongly disapprove of her. Of course to really qualify as polarizing, I would want to see someone have a “U”-shaped distribution on this four-point scale — more strong approval than somewhat approval, more strong disapproval than somewhat disapproval.
We see here that fully forty percent of the population is in one or the other “somewhat” category. I myself would have said I have a somewhat favorable view of Clinton and I think that, despite the “polarizing” label, this is actually pretty common.