As I noted before, homeschoolers are helping Huckabee and will be key to his victory.  It is one thing for the winners to say so, it is another for the vanquished to acknowledge.  In the story from Byron York over at National Review, Romney spokesperson Eric Fehrnstrom noted:

We're going up against a loose confederation of fair taxers, and homeschoolers, and Bible study members, and so this will be a test to see who can generate the most bodies on caucus day.

According to entrance polling, nearly 60% of Iowa caucus goers identified themselves as "Born-Again or Evangelical Christian".  Huckabee pulled 46% of those Christians.  Huckabee also did well in the majority of all the demographics.