An interesting hypothesis. It's clear that the mainstream of the Republican Party is insane, disconnected from reality on science and economics. Are we therefore more vulnerable to stories about "moderates" so that we don't have to admit that one of our two major parties is completely off that rails? (This is not to say that the Democrats are in any way on track.)
How the media created Chris Christie
I think the mainstream media and its dominant pundits are unable to take in exactly how far to the right the Republican Party has swung in the last decade, and so they need to invent “moderates” to keep from writing over and over about the party’s departure from political sanity. And when their moderates either show themselves as extremists, as Christie has repeatedly, or else as severely flawed politicians, as Christie has lately, those pundits either ignore it or rush to rescue them over and over.