W. J. Cash, in 1940:

Proud, brave, honorable by its lights, courteous, personally generous, loyal, swift to act, often too swift, but signally effective, sometimes terrible, in its action -- such was the South at its best. And such at its best it remains today, despite the great falling away in some of its virtues. Violence, intolerance, aversion and suspicion toward new ideas, an incapacity for analysis, an inclination to act from feeling rather than from thought, an exaggerated individualism and too narrow a concept of social responsibility, attachment to fictions and false values, above all too great attachment to racial values and a tendency to justify cruelty and injustice in the name of those values, sentimentality and a lack of realism -- these have been its characteristic vices in the past. And, despite changes for the better, they remain its characteristic vices today.

In the coming days, and probably soon, it is likely to have to prove its capacity for adjustment far beyond what has been true in the past. And in that time I shall hope, as its loyal son, that its virtues will tower over and conquer its faults and have the making of the Southern world to come. But of the future I shall venture no definite prophecies. It would be a brave man who would venture them in any case. It would be a madman who would venture them in face of the forces sweeping over the world in 1940.

But the South was still voting Democrats into House and state governments until the 90s. The Democrats lost the South's presidential votes with the Civil Rights Act, but it wasn't until Newt that the South went solidly Republican. Wikipedia has nice tables of presidential and gubernatorial. It took the Republicans Party a long time to really take over here, and I think it's naive to chalk their eventual success, decades later, up as a direct result of the civil rights movement.