In retrospect, which were realigning elections?

[Joe McCarthy Was Right]

An interesting theory I read (from Sean Trende) was that the Obama coalition was just a narrower but deeper version of the Clinton coalition (losing Appalachian whites, but winning more of the black and youth vote and turnout), thereby making 1992 the big realignment election. Also in that theory, the New Deal coalition only lasted in presidential elections until 1944, with Truman's coalition more closely resembling Woodrow Wilson's than Roosevelt's. Nixon's base was just an extension of the Eisenhower coalition that lasted until 1988.

1992 doesn't really resemble 1976. I think at least 21 states voted differently. 1952 resembled 1980 at least at the county level. Therefore, 1952 would be the other major realigning election.