I think this issue is "muddying the waters" regarding the presidential race. Orthodox Christians view any religion that does not embrace the orthodoxy of Christianity (Trinity, Diety Of Christ, Soul, Hell) to be a cult. Their definition of cult is not so much an isolationist group under the influence of a single leader or leadership that is high control, but rather that it is not "Christian" under the definition of orthodoxy. Using that definition, Robert Jeffress, was correct regarding Mormonism in his "definition" of a cult (this would also apply to JW's, Christadelphians, etc.).
Ralph Reed (former head of the Christian Coalition), who has never been know as a liberal Christian, stated it rather clearly when addressing the issue..."we aren't electing a Senior Pastor or Pope, we are electing the President, a political leader", thus his Mormonism shouldn't be a consideration of his qualifications, but rather his political agenda should drive that decision among voters.
I have no doubt, that if given the choice between Obama and Romney during the election, the majority of Evangelicals would vote for Romney despite their disagreement with his religious affiliation.