I also want to add that the belief that black people were "descendants of Cain" is said to be widespread and doctrinal until not that long ago.
Mormonism is Weirder and Cultier than Ever Acknowledged in Print
Until 1990 the Mormon temple ceremony had all participants recite in unison and pantomime their own executions by throat-cutting and disembowlment as the penalty for revealing the secret password and handshake necessary for entry into heaven. (Mitt and Ann Romney did this, folks. . .do you really want his hand on the button?)
Also until 1990 the ceremony revealed it's incipient misogyny and bigotry in its requirement that women take an oath of submission to the will of their husbands and the assertion that the paid clergy of all Christian denominations were employees of Satan.
Mormonism's racism as original religious doctrine is made clear in, among many other examples, the fact that until the mid 1970's the Book of Mormon labeled the forebears of the American Indians a "dark and loathsome" people who had been cursed with a "skin of blackness" for their sins and who, if they would repent, could become "white and delightsome" like their righteous cousins, the Nephites.
And these are only the tip of the Mormon whacko iceberg. Don't know about you but I sure would want to know if a presidential candidate believes or ever did believe such malignant craziness.