A Sin Not to Vote for the Godly Man

Dr. James Dobson:

"If you can find a politician who understands the institution of the family, who wants to protect children from immorality, who understands that we are at war with those who want to destroy us, and who understands that liberal judges are undermining us and need to be reined in...and if you can find a politician who lives by a strong moral code and believes in Jesus Christ ... if you can find such a person, it would be a sin not to vote for him."

http://blog.christianitytoday.com/ctliveblog/archives/2008/02/is_not_voting_a.html

And thus a sin not to vote for (or endorse) Gov. Mike Huckabee?

Or if not, on which standard mentioned above does Huckabee fail the test?