I could never conceive of RMN as a tragic hero, in either the Aristotelian or Shakespearean sense. In both instances, the tragic protagonist has to be someone who falls from an exalted state to his own ruination, due to a tragic flaw in his own makeup (hubris), i.e. Oedipus's tendency toward rash behavior, Hamlet's indecisiveness, and so on. The mere fact that Nixon benefitted from a plurality of voters would not, to my mind, qualify him as coming from an exalted state. What deed or deeds did he ever perform that could possibly qualify him as heroic? Macbeth was ambitious, ultimately to the point of murdering his rivals and even innocent women and children. But it's well established that, before his tragic fall, he served with utmost distinction as a brave warrior, risking his life for a just cause. It's interesting to consider whether, in the present era, there can be such a thing as a tragic hero. The literary critics I've read seem to suggest not. Unless, that is, we alter the concept to encompass the common man. Then Willy Loman comes to mind, along with some of O'Neill's protagonists. (Care to comment, WO'N?)
Who is there, in our time, that could be viewed as a tragic hero? Pete Rose, perhaps? Some dot-com CEO?