Many of those who cast a ballot for Obama were voting against the really horrible Republican nominee, and didn't realize how evil and dangerous Obama was. Those people might reasonably be persuaded to vote against Obama this time around. There are, however, a significant fraction of voters who view their own wealth outlook as being purely a function of how much money the government gives them. Nothing that any Republican could possibly say is apt to win votes from such people, and no good can come of appeasing them.
Yet Romney was even worse, and came in third in 2008.
Romney’s list of Americans that he has denigrated and insulted is almost total, but there is no nicely packaged 47% for the ignorant fool to attack, he is clueless.