Off the bat, I'd say about a quarter of right-wingers are overtly or covertly racist. Probably 10% of left-wingers, mostly covertly or in denial about it. And when I refer to alt-right as lite (soda, not beer, but I guess it amounts to the same metaphor), I mean that the modifier "alt" was added initially in order to distinguish them from the more outwardly detestable segments of the right, but then ended up being applied for all of the right. Frankly, I've not heard a reference to the right, without alt- in any conversation unrelated to driving in at least a year.