MARGINS OF VICTORY
Republican Presidents Reelected During the Last Hundred Years
        President        Popular Vote        Electoral Vote
1904        Theodore Roosevelt        17%        196
1956        Dwight D. Eisenhower 16%        384
1972        Richard M. Nixon        23%        503
1984        Ronald Reagan               18%        512
2004        George Bush               2%        34

          Source: http://www.nybooks.com/articles/17690

This article in the New York Review of Books is an interesting study on the ebb and flow of beliefs behind Bushie's re-election. I recommend it as a good read.

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