The Senators and Representatives before mentioned, and the Members of the several State Legislatures, and all executive and judicial Officers, both of the United States and of the several States, shall be bound by Oath or Affirmation, to support this Constitution; but no religious Test shall ever be required as a Qualification to any Office or public Trust under the United States.
http://www.archives.gov/national-archives-experience/charters/constitution_transcript.html
Ummm, the Constitutional "no religous test" standard applies limits to the GOVERNMENT, not to the people. This was written to avoid a religious majority in Congress keeping out duly elected officials they disagree with religiously.
We as the people can vote or not vote for anyone on the ballot, for whatever reasons we please... that's what freedom is all about.
I for one could not vote for a member of a religious cult, no matter how nice they are. I know a fair amount about Mormonism, it is not a Christian denomination, rather it is a heretical cult, which came out of Christianity. It has a different canon of scriptures, different definition of God, a different definition of Jesus Christ, different understanding of history, etc., etc.--not to mention its historical roots in polygamy (yes I know, banned since 1880). Of course they have the right to believe anything they want without harassment--but I also have the right to use my best judgment in who to vote for...