Catholics. Evangelicals. Mormons. As the South Carolina primary inches closer and closer, Robert P. Jones of the Public Religion Research Institute discusses religion and the GOP race. Then, Emily Bazelon of Slate reviews how the rules have changed for Super PACS. Plus: nutrition expert Marion Nestle on the news that Food Network star Paula Deen has type 2 diabetes; airport security in this week’s Crosscheck series with Jad Mouawad of The New York Times; and learning the guitar at 40.