” ... gay relationships will be legal.”
The already are legal.
Redefining marriage — that is not yet legal in all states. Indeed, it is folly.
Newt was his opponent and fought a good battle so he 'sees' how the republican voters feel - they overwhelming sided with evil Romney and believe Romney's lies/deception about Newt and the other candidate Santorum is a known 'take it for the team, The GOP. He is one of them and will betray those who vote for him every time.
So it's not rocket science for Newt to speak about what he has first hand witnessed.