HMMmm...
What's wrong with voting against a MORMON because he's a MORMON?
If you think that a Mormon, by his nature, cannot represent your political interests to your satisfaction, then by all means vote against him. Similarly, other people may decide that people of your brand of Christianity are unfit, by their nature, to hold office and vote against them, and that would be their right as well.
Just don't expect to convince me to agree with you any time soon.