How often has it occurred that a presidential candidate has won each of the four census regions or even every single division of the United States?
My dataset only goes as far back as 1868, but since then, this has happened 7 times:
1928: Hoover's worst was West South Central, which he won by 2.6%
1932: Roosevelt's worst was New England, which he won by 0.8%
1936: Roosevelt's worst was New England, which he won by 7.4%
1972: Nixon's worst was New England, which he won by 5.8%
1980: Reagan's worst was East South Central, which he won by 1.0%
1984: Reagan's worst was Midatlantic, which he won by 9.4%
1988: Bush's worst was New England, which he won by 0.2%
Near misses:
1872: Grant lost West South Central by 0.3%
1940: Roosevelt lost West North Central by 3.3%
1956: Eisenhower lost East South Central by 2.5%
1992: Clinton lost West South Central by 0.8%, East South Central by 1.0% and Mountain by 1.8%
1996: Clinton lost West South Central by 0.05%, East South Central by 1.6% and Mountain by 3.8%
I also manually checked 1852, because it was the only plausible candidate between 1868 and the consolidation of the lower 48: Pierce lost East South Central by 4.9%.
It is interesting to see which landslides managed this and which didn't - it shows how different regions have become more or less politically polarized over time (acknowledging that these regions are subpar for political analysis):
