Backwards, that is.
Here's a transcript of Kennedy's speech explaining why his Catholicism shouldn't be an issue in the election. A really short summary would be: Separation of Church and State should (and will with me) be absolute. I don't speak for the Church and they don't speak for me. There are bigger issues at stake.
Now, at least half of the candidates seeking nomination use their faith to court voters. They will (or at least say they will) make decisions based on their faith. Some of our current elected officials have even made decisions based on their faith and not on the Constitution.
Different religions often emphasize similar values and those common values are ones I think are good ones for elected officials to ascribe to and want to bring to the office. (Talking about honesty, peace, charity, stewardship, tolerance . I didn't say all sects of all religions emphasize all of them.) Therefore, I have no problem with an elected official being religious. I have no problem if their faith informs their decision making. BUT in the end whether to sign or veto a bill, whether to normalize relations with a country, whatever, has to be decided on the best interests of the country and the constitutionality of it, not whether your pastor (rabbi, imam, priest, guru,...) says it is right.