This is truly a sucky-butt article.
For starters it doesn’t say when JD said that on “p m s n b c,” and it only quotes JD as saying:
“I am going to support the Republican nominee,” Hayworth said. “I fully expect to be that nominee.”
I seriously doubt that he said “I will support McCain.”
FALSE TITLE! FALSE CLAIM!
He was on MSNBC just before or after he left his radio show. Haven't heard of him being on since. It looks like this entire Atlantic article cobbles together three week old news and presents it as if it's something new.