You mean like Strom Thurmond, Ronald Reagan, Jesse Helms, Condoleezza Rice, Mike Pence, Rick Perry, Phil Graham, Jeane Kirkpatrick, George Wallace Jr and David

You mean like Strom Thurmond, Ronald Reagan, Jesse Helms, Condoleezza Rice, Mike Pence, Rick Perry, Phil Graham, Jeane Kirkpatrick, George Wallace Jr and David Duke? All switched from Democrat to Republican and are either notable for high political office, or being racist. In some cases, both. It is true that Civil Rights in 1964 began the switch. But it didn't really get going until Civil Rights Act (1964) really alienated Southern Democrats. Starting with Nixon's Southern First strategy, Republicans worked to appeal to them. With the rise of the religious right under Reagan there was a mass migration. You can see https://www.history.com/news/how-the-party-of-lincoln-won-over-the-once-democratic-south https://www.history.com/news/how-the-party-of-lincoln-won-ov... to see that I'm not simply making this version of history up. Did you have any references to it being just a "big lie"?