When Santorum drops out, the race is over.
It would be pretty delusional to think that, if Santorum can’t win his home state, that some how Gingrich (currently polling in single digits) would actually beat Romney in Pa. if Santorum dropped out.
You really need to not put so much weight on polls...which you seem to mention frequently. But do recall how low Rick was trending before Iowa....until the media ran people needed to give him a "second look".
I don't underestimate the power of the media to influence or drive this primary ....if Santorum was to drop out before Pa. which he likely won't, then I never underestimate the hand Newt might play....ever.
However Romney's apparently leading in PA currently....according to polls...or which ever one might make him look better or worse you're looking at. Polls are like looking into an 8 ball for the future. Win or lose it's still quesswork.