The fact that this guy ran for Congress is meaningless. Anyone can run, even conspiracy theorists who base their arguments on bad science, illogical conclusions, and utter lack of evidence. Hoagland's touting of this guy's "endorsements" is typical of his tactics. He gives enough information to make his arguments sound legitimate, but holds back the real information you need to make an informed decision.

For example: what was Sadler's platform for running (some of that, but not much, can be gleaned from his website)? How much of the vote did he get? How much experience does he have investigating scientific (and non-scientific) claims? These are all relevant, and pertinent.

Hoagland is clearly using this guy as an "argument from authority", so questioning his authority is not only fair, it's important.