I think the premise in that article is based on some pretty tenuous information.
An anonymous Romney advisor? A comment from 45 years ago, during the 1968 Republican primaries, taken out of context from a book written by Boston Globe reporters? Romney was all of 20 at the time.
(Odd how young behavior is so significant for Republican presidential candidates, but not Democratic ones.)
This isn't about what Romney actually thinks. This is about the Democrats launching yet another phony narrative when so many others have been blowing up in their faces.
Most Americans have a pretty good idea which party actually has contempt for the "bitter clingers."
What you are seeing in that article is Chait's views of conservatives, not Romney's.