Not sure what to make of this article at Discover mag - I'm sure it's tongue-in-cheek to some extent, but it seems to me that proposing the idea that people are more inclined to dislike gay marriage because they're easily disgusted is going to arouse the ire of the perpetually aggrieved.
People react very differently to disgusting situations than to other daily life events, and it’s thought that this may have evolved as a way of protecting ourselves from parasites. But such hard-wired responses also have far-reaching effects on modern life. For example, this paper suggests that differences in disgust responses may influence one’s political affiliation and views on gay marriage.Here's a link to the abstract: Disgust sensitivity and the neurophysiology of left-right political orientations, which includes this:
In this article, we demonstrate that individuals with marked involuntary physiological responses to disgusting images, such as of a man eating a large mouthful of writhing worms, are more likely to self-identify as conservative and, especially, to oppose gay marriage than are individuals with more muted physiological responses to the same images.