No one has run for presidential office for so long while conveying so little about the reason for doing so as Romney has. The purpose of Romney’s candidacy is simply to win the election, which is as dull and ordinary as one can imagine, and there is not really any pretense that Romney’s candidacy serves a “larger purpose.” People cannot put faith in Romney, because he is thoroughly untrustworthy and prone to saying whatever it is he thinks people want to hear. To the extent that a lot of non-Republicans are willing to give him a hearing, they assume that the policies he is proposing during the campaign cannot possibly be the policies he would pursue once in office. When he says, “I will move for this and this,” the common reaction is to assume that Romney will not so move.
Romney is the embodiment of everything Americans claim to dislike about national politics. He is both a fierce partisan and lacking in firm convictions. If Romney does end up winning, that will be a good indication that a majority of voters isn’t interested in the meaning or purpose of his candidacy. It will mean that enough voters are dissatisfied enough with the incumbent that they are willing to tolerate just about anyone as a replacement.