And he should know, since he's been both a paid contributor for them as well as a subject of their coverage:

Gingrich said: "I think Fox has been for Romney all the way through. In our experience, Callista and I both believe CNN is less biased than Fox this year.

"We are more likely to get neutral coverage out of CNN than we are of Fox, and we're more likely to get distortion out of Fox. That's just a fact."
http://www.guardian.co.uk/world/2012/apr/12/newt-gingrich-co...

Fox News struck back, calling him a "fat Right Wing hack." Just kidding. No way they'd say that, because then they'd be accused of being accurate.

Fox hit back in a strongly personal attack. In a statement provided to the Guardian, it said: "This is nothing other than Newt auditioning for a windfall of a gig at CNN – that's the kind of man he is.

They did say that. More at the link.

Not seeing this particular controversy covered at Drudge, Fox, or Retire Early Deranged. Wonder why?