We paid too much attention to the size of the crowds turning out for Obama. It is true that he got larger and generally more enthusiastic crowds than Clinton, but that did not translate into more votes. A significant minority of the people (perhaps 30-40 percent) who attended Obama rallies were undecided voters. (We know this because he usually asked for a show of hands at the beginning of the rally.) It is now clear that he did not always make the sale.