COUNCIL BLUFFS, Iowa, July 3 — Dell Collins teaches an adult Sunday school class at his evangelical church in central Iowa, and he recently took his students through a series of lessons on the Book of James and its repeated exhortations to put faith into action.
But Mr. Collins is grappling with just how to apply his beliefs when it comes to picking a favorite from a Republican field in which the leading contenders each face serious obstacles to winning over Christian conservatives.
“Do you go with your heart or with your head?” he said. “My first choice is with my heart, but you also have to be realistic.”...