Due to his popularity bump after 9/11, many political commentators felt President Bush would win reelection in 2004 by a substantial margin, if not an outright landslide. As late as mid-2004, many felt Bush would, at the very least, win reelection by carrying states like Pennsylvania, Michigan, Wisconsin, and others that the Republicans hadn't won since in the 1980's.
Alas, this was not to be. Democratic nominee John Kerry steadily chipped away at Bush's poll numbers until we were left with a very competitive race. Ultimately, Bush won anyway, but Kerry held him to less than 300 electoral votes and a barely two-point margin of victory.
So, how can this be changed? With a point of divergence no earlier than January 1st, how big a victory can the Republicans realistically get in the electoral college? What potential Democrat candidate would be the weakest (John Edwards? Howard Dean?), and how would the campaign need to go? Can Bush win in a 1964/1972/1984 landslide, or realistically would he "only" be able to win with the states he won in 2004, plus Pennsylvania, Michigan, Wisconsin, etc?