Graham Platner is supposed to be finished. The Democratic nominee for Senate in Maine faces a rape allegation, Bernie Sanders and Elizabeth Warren have pulled their endorsements, and the Democratic Senatorial Campaign Committee has told him they won't spend any money on his campaign if he stays on the ballot. He has until Monday to withdraw before Maine law locks Democrats into running him in November, whether they like it or not.By every conventional measure, Platner should be packing his bags.Instead, he is negotiating. Platner has reportedly told the Maine Democratic Party that any replacement must match his own ideological...