You call that an attack. I call it the plain truth. Newt's presence just make's Romney inevitable.
The Gingrich voters generally do not like Santorum, or they would be voting for Santorum. People just assume that the Newt voters would go Santorum, and that just isn’t true. Might also add, the voters who support Newt Gingrich are not looking for just anyone who can beat Obama, they are looking for experience, depth, and intelligience, which of course, just happens to be what is needed to beat Obama.