The Portland Press Herald lined up four people to watch the debate and grade the candidates' persuasiveness, command of the details and stage presence. We've averaged those scores to give each candidate an overall grade. An "A" is worth 5 points, a "B" is worth 4 points, a "C" is worth 3 and a "D" is worth 2. The judges were chosen from a group of Maine voters who participated in a statewide public opinion poll for the Portland Press Herald in September.