Until Mitt Romney, no major party has nominated a Mormon as their presidential candidate. And Americans are still a bit uneasy about his religion: Today a new Gallup poll shows that nearly 1 in 5 (18 percent) of Americans say they will not vote for a Mormon presidential candidate. Are Mormons disproportionately disliked? Is this kind of bias expected? Here’s how Americans feel about electing presidents from other minority groups (and women).