WASHINGTON — Memo to Democrats: You will be defined by President Obama whether you like it or not, so you might as well embrace him for the benefits he can bring you. Memo to Republicans: Talk a right-wing game in your ideological magazines and at your tea parties if that makes you happy. But to win elections, your candidates had better look like middle-of-the-road problem-solvers. Those are the two outstanding lessons from the campaigns for next Tuesday’s governors’ races in New J