If by, "left with" you mean their respective ratings for their last year in office you're right. That's like saying Hank Aaron "left MLB with" 10 home runs (1976, his last year).
IMHO, a more realistic use of the term "left with" would be their aggregate lifetime ratings for their congressional careers which puts Newt at 90% and Santorum at 88.1%. Given that Newt was a Representative from a safe conservative district, and Rick was a Senator from a swing state, the only really shocking thing about that comparison is why Newt's wasn't much higher....
No, you're intentionally ignoring the fact that Santo didn't vote like a conservative, no matter what district he came from. That's why HIS rating wasn't higher when he left office. Franky, with his record, I don't know why he rated as high as he did.
"Shocking", huh?