Lafferty, apparently echoing Fred Barnes, suggests that the people who doubt Palin's intelligence are people who have never met her or spoken with her. Lafferty, on the other hand, has met and worked closely with Palin as a consultant for the McCain campaign.* She describes Palin as "very smart," in fact, "a brainiac." Palin is "thoughtful, curious, [and has] a discernible pattern of associative thinking and insight." She has a photographic memory that Lafferty has seen in action.
If you disagree with Sarah Palin on policy issues, that's fine. You shouldn't but you are entitled to your opinion. But if you plan to vote for Barack Obama and Joe Biden because you think that John McCain picked a dimwit as his running mate then you are either simply uninformed or possibly a dimwit yourself.
(*Why the McCain campaign is consulting with strident, "Pro-Choice" Democrats is a question for another day.)