Mitt Romney is a Mormon, and don't let anybody tell you otherwise. Even though he talks about Jesus as his Lord and savior, he is not a Christian. Mormonism is not Christianity. Mormonism is a cult.
Quite frankly, I would prefer to have a non-Christian like Mitt Romney who at least pretends to embrace biblical principles over a professing Christian like Barack Obama who embraces very unbiblical positions on abortion.