You have the right take, the switch was made in 1936, not the 1960s.
The switch was a complete and instant reversal, in 1932 the black vote was like it always had been, FDR got his 23% while the GOP got its over 70% which were typical numbers, but suddenly and permanently the black vote reversed itself in 1936 and FDR got over 70% and that was it.
“suddenly and permanently the black vote reversed itself in 1936 and FDR got over 70% and that was it.”
I wonder how he did that.
In a way, he was the “great White father” to both Blacks and Whites. My liberal mother-in-law glorifies FDR. Her husband loved “Uncle Joe.” Don’t misunderstand. These nice people aren’t Marxists or communists, just Democrats.