In a recent study;

In one of the new studies, Cornell University psychology professor David Pizarro and colleagues surveyed 181 U.S. adults from politically mixed swing states. They used a Disgust Sensitivity Scale (DSS), which offers various scenarios to assess disgust sensitivity, as well as a political ideology scale. They found a correlation between being more easily disgusted and political conservatism.

Then they surveyed 91 Cornell undergraduates with the DSS, as well as with questions about their positions on issues including gay marriage, abortion, gun control, labor unions, tax cuts and affirmative action. Participants who rated higher in disgust sensitivity were more likely to oppose gay marriage and abortion, issues that are related to notions of morality or purity.

The results are detailed in the journal Cognition & Emotion.

In a separate study in the current issue of the journal Emotion, Pizarro and colleagues found a link between higher disgust sensitivity and disapproval of gays and lesbians. In this research, they used implicit measures, which assess attitudes people may be unwilling to report explicitly or that they may not even know they possess.

Also;

Liberals and conservatives disagree about whether disgust has a valid place in making moral judgments, Pizarro argues. Some conservatives think there is inherent wisdom in repugnance, that feeling disgusted about something - gay sex between consenting adults, for example - is cause enough to judge it wrong or immoral, even lacking a concrete reason, Pizarro explains. Liberals tend to disagree, and are more likely to base judgments on whether an action or a thing causes actual harm, he said.

and finally;

Research published in 2007 in the Journal of Applied Psychology found that people who think of themselves as having high moral standards often become the worst cheats because they pursue what they believe to be a moral end at all cost

I always wonderd why I feel so disgusted listening to consevatives. Now I understand that it is a simple case of countertransference ;)