The senate is a bigger problem than the house, and no one is worse than Take-the-money-and-run Specter.
And Gingrich's endorsement is certainly worse than Santorum's, if for no other reason than Santorum was heavily pressured by Karl Rove and George W. Bush to back an incumbent Republican from his own state. Nobody pressured Newt to endorse a socialist RINO, he gleefully did so on his OWN as a private citizen when Santorum and other conservatives were supporting Doug Hoffman. What's more, Newt lashed out and attacked anyone who supported Hoffman. I don't recall Santorum attacking Toomey supporters.
Unlike Santorum's endorsement, it wasn't Newt's only time backing a RINO. He also backed RINO Joe Schawz over conservative Tim Walberg. And if you want to excuse your hypocrisy by claiming the Senate races are more important, he also backed establishment incumbent Republican Robert Bennett over tea party challenger (and now Senator) Mike Lee.
I don't excuse Santorum's endorsement, caving to the GOP establishment was a mistake on his part. But Newt's fans certainly excuse Newt's endorsement, which speaks volumes about what kind of "principles" (or more actually, lack of principles) he has and disdain for the little people.
Why Newt's fans think they'll get anyone on their side by throwing stones in Newt's glass house I'll never know. Newt is the left of Santorum on both his endorsement record, as well as record on "fiscal conservatism". It's hillarious when they trash Santorum as a RINO lover and an economic socialist for failings that aren't nearly as bad as Newt's.