Scott Yenor reviews a new book on that topic, but I’m not entirely convinced on its main point:
Paul contradicts this liberal narrative. Personal acquaintance with homosexuals, for instance, is more an effect of political opinions than a cause: people have contact with homosexuals because they first admire them. Furthermore, liberals do not consistently tolerate or affirm all of those they come into contact with. Those who come to have favorable views of homosexuality and same-sex marriage continue to have unshakable and deep prejudices against poor whites and Christian fundamentalists, even after they come into contact with them. Such “liberals” are, Paul shows through survey data, among society’s biggest haters, in fact.
I doubt many of those people have truly “come into contact” with “poor whites and Christian fundamentalists” in their daily lives; their opinions on them are acquired through the media.