It's called ad hominem, a classic logical fallacy, and means name-calling, slander, carrying the argument "to the man" rather than debating the topic.
Like trying to affix the label "Muslim" a president who's getting things done. A recent headline asks if people will vote for a person they think is a non-Christian. Fiorella thinks that's a matter of putting the cart before the horse. The ones who think Obama is a Muslim are people who wouldn't vote for him in the first place.
People believe what they want to believe, then manufacture reasons to support their viewpoints.