John notes below some recent survey evidence, and incipient media panic, suggesting that Trump is rallying. Let's step back from the day-to-day numerology of polls and headlines and consider presidential elections from a long-term point of view—a 'field theory,' if you like. Over the last 100 years, only three incumbent presidents were defeated for re-election: Herbert Hoover in 1932, Jimmy Carter in 1980, and George H.W. Bush in 1992. (I
