In my experience, people who've read Ayn Rand's books either love them or hate them. I'm one of the few who fall somewhere in between.
Assuming the author means what he's saying, that should read:
In my experience, people who've read Ayn Rand's books either fall into one of two categories, or they don't.
Of course, given that the author is SC Governor (for now) Mark Sanford, a man with a proven inability to distinguish "Appalachian Trail" from "Argentina," perhaps that's an assumption we shouldn't make.
(Hat tip to Charles Pierce, who raises the perfectly valid question: Why is Newsweek helping Sanford revive--or at least prolong--his dwindling political fortunes by publishing one of his high school book reports?)