Brent has never shown himself to be a fan of Doctor Who. In fact, the series has never been mentioned in the comic before. So why reference it now? Oh, right...because Kurtz has suddenly become a fan and thus one or more of his characters are now fans by proxy. /sigh.
Now, if the strip were Kurtz himself voting for the Doctor, that'd be a horse of a different color.
The old woman's dialogue feels pretty forced in the second panel as well. Is there really a reason for her to tack on "...for president of the United States?" to that sentence?
The punchline fell pretty flat for me as well. I mean, there could have been some witty comment but instead we get a very tired (if you're a who fan) "just The Doctor" joke.