IMO, the multi-million dollar tv and radio campaigns with the "I'm a mormon" and other PR gambits by the mormon church have succeeded in waking up a section of the American public to the arcane doctrines and beliefs of the mormon church...unintended consequences.
I can see a person who knew nothing about the sect watching one of those commercials and thinking, "Duh, how weird is that!.
Also, the continued attempt by mormons to force Christians to consider mormonism as just another Christian sect when it is not has, as you can see in posts on FR, infuriated many Christians.
The Flying Inmans have been working for several years to provide the facts to FReepers. I think that SC indicates the probability that Mitt Romney cannot receive the votes of the Christian and Evangelical base.
Well, we still have a lot of work to do.
I think the polls indicated in the Fall that something like 60% people still didn't know that Mitt Romney was a Mormon.
The CNN Exit polls referenced in this article indicates that about 48% of all South Carolina GOP voters were influenced enough about Romney's religion to include that as one factor among others to not vote for him.
[How I arrived @ 48%: 60% said they took religion into consideration; 80% of them didn't vote for Romney...hence about half of the state GOP-wise]
That either means...
More and more people are becoming aware of what Mormonism is...
Or GOP voters have always had a more in-depth understanding of how bad Mormonism is...
...Or it's a combo of both.