Where Trump gained

This is fascinating, showing the change (according to exit polls) from 2012 to 2016. So effectively how Trump did compared to Romney.

He massively picked up votes of non-college whites. But he also increased the vote with Asians, Hispanics and Blacks. Overall the white vote for him only up slightly.  A 5% increase with men.

He lost support with women (but not much), over 65s, Jewish voters, gay voters and white college voters.

The big divide change is the white vote polarising between college and non college so much more.