Because Americans will vote much more on "feel" rather than "think", (charisma vs. issues). It was this way in 1960, in 1976, particularly in 1980/84, and again in 1988, not to mention 1992 and 1996, and then 2000 and 2004. In each case, the less charismatic person lost, not necessarily a battle over policy.
True. Charisma will carry the day at the end. That is why Hillary Clinton cannot be President, she is the most uncharismatic person to run for President ever, not to mention that she is the rudest, meanest, most arrogant, and most fake.