There are definitely some very intelligent people who are religious, scientist actually (which raises more questions) I know a few personally. However, the depth of their belief is interesting;
They do not believe in the Bible word for word, they understand it was written by man, and therefore flawed. It was an interpretation of stuff that man doesn't and wasn't meant to understand. They hold faith in the fundamentals, they don't disbelieve evolution, or the creation of the universe - they just believe that’s how it happened and not why. The 'why' is where their faith kicks in.