The framing of facts as "smears" is ridiculous, it's literally his self admitted past. He is a war criminal who worked as a Blackwater mercenary that was responsible for Abu Ghraib torture and prisoner abuse. He had probably the 2nd most recognizable nazi symbol behind the swastika, a totenkopf, tattooed on his body.
The reason why these "smears" didn't work is most Maine voters are functionally imperialist and nazi aligned whether they would admit it or not.