Graham Platner, a veteran and oyster farmer from Maine who is running as the Democratic candidate for the U.S. Senate, is currently in the national spotlight due to Reddit posts from 2018 and a tattoo of a skull-and-crossbones, which is associated with Nazi symbolism. When he launched his campaign in August, the 41-year-old former Marine and combat veteran presented himself as a defender against “the oligarchy” of billionaires and “corrupt politicians.” He also raised $3.25 million in the first six weeks of his campaign, according to Reuters, and secured the support of Sen. Bernie Sanders (I-Vt). With less than two...