Graham Platner is sitting down for a bite between campaign events in his dining room overlooking Frenchman Bay, the scenic Down East waterway where he once farmed oysters, and more recently takes reporters on boat rides to talk about his unexpected political ascent. Sun streams into the room, which is decorated with family photos and wooden Easter eggs painted pastel shades. Suddenly Platner’s black Lab, Zevon (named after rock star Warren), lunges at the tinfoil-wrapped breakfast sandwich on