In other words, he would be rather working-class than middle-class, and as such quite likely to be a staunch democrat (until when? Wilson entering WWI against Germany? Hoover/ Eisenhower, American Germans both becoming US Presidents on a Republican ticket? Post-Kennedy / Civil Rights party realignment in the US?).
The party realignment dodn't occur over civil rights, it wasn't until 1980 that the South became strongly Republican and not until 1992 that the Dems' current areas or strength started consistently voting that way.
The South was Goldwater's best region in 1964, and it's almost impossible to argue that wasn't because of his opposition to the Civil Rights Act. (Even if his opposition was more principled than your average Southerner's.) At a presidential level, 1964 is in fact
the signal turning point, with Carter being an aberration which can be attributed to his blatantly evangelical campaign. Obviously, local elections were a lagging indicator, and took longer to switch.
It would be most accurate that the realignment took a
very long time, as it started all the way back with Al Smith and took until the 1994 midterms to really resolve itself.