When did the parties switch platforms?

[pbrower2a]

The Democratic Party was the catch-all party before the mid-1960s split between agrarian reactionaries and racist populists (the latter rather liberal on government spending). The North and West had liberal and conservative wings in both parties.

Signs of the weakening of the Democratic Party began as Strom Thurmond split a third Party in a protest against the baby steps of Harry S. Truman on racial equity as early as 1948.

In the 1960s, Democrats sought to win the votes of Southern blacks But such built an unwieldy coalition of people with opposite purposes in politics. Unwieldy coalitions break. Southern whites slowly drifted R.

Almost the only liberals in the South are now blacks. Thus places like Atlanta, Birmingham, Memphis, and New Orleans are very liberal -- as liberal as Northern cities -- but not large enough to offset the rest of the states.

Another aspect of the switch is that Northern suburbs, which used to be bastions of conservatism when they still had rural qualities when newly built, became liberal as they became more urban than rural. Suburbs of New York, Boston, Philadelphia, Baltimore, Washington, Cleveland, Detroit, and Chicago are now old enough that one must be old (60 or older) to remember them as attempts to bring some rural character to the fringes of great cities. The original infrastructure is getting old and has huge costs of repair or replacement.  The original lanes suited to thinly-packed tract houses now must often be widened (at much cost) to accommodate the densely-packed apartments that have even more cars per square mile. The older suburbs of places like St. Louis are getting legitimately urban, and the vote changes to match that reality. The newer suburbs of Atlanta, Dallas, Houston, and Phoenix (Phoenix isn't, strictly speaking, "Southern", but its suburbs are very conservative)   have no such problems -- and they remain bastions of political and economic conservatism. Southfield, Michigan is very different from Plano, Texas. But give time and places like Scottsdale, Arizona and Marietta, Georgia will become about as liberal as Southfield, Michigan -- at which time the game is up for the GOP coalition that it now has.

   

[pbrower2a]

I can't show this map often enough for my liking. But here we go:

I here contrast Dwight Eisenhower to Barack Obama. Ike won Mormon country and the High Plains. But just think -- Ike won everything in the North and West, winning two states together (Massachusetts and Minnesota) that Republicans have never won together -- twice. In 2012, although winning a respectable 332 electoral votes, did not win a single state that Ike did not win twice.

(Sure, there will always be a significant overlay of any winner over the landslides of FDR in 1936, LBJ in 1964, Nixon in 1972, and Reagan in 1984 -- but the Obama wins make more impressive overlays against those of Eisenhower) because Ike and Obama both won the single states that Nixon and Reagan lost in 49-state landslides and the two tiny states that FDR lost in 1936.   

 
gray -- did not vote in 1952 or 1956
white -- Eisenhower twice, Obama twice
deep blue -- Republican all four elections
light blue -- Republican all but 2012 (I assume that greater Omaha went for Ike twice)
light green -- Eisenhower once, Stevenson once, Obama never
dark green -- Stevenson twice, Obama never
pink -- Stevenson twice, Obama once

No state voted Democratic all four times, so no state is in deep red.