Santorum can also use his religious beliefs only so far before he, say, upsets civil libertarians or non-Catholics (there're some Christian denominations in the U.S. who still don't like the Church for some reason or another). The Catholic voting bloc in the U.S. is large indeed but they all mostly vote Democrat (the Kennedys, Irish Catholics, were all big-time Democrats). These are your mainstream Catholics, the majority, and not the Catholic traditionalists who probably vote Republican or belong to some sort of state conservative party. Santorum has done well among Christian conservatives (mostly Protestant) and even among some Orthodox Jewish groups- vastly better than that posterboy of corruption Gingrich.
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