That the Republican Party has spent the last 45 years making coded and uncoded appeals to white racism is self-evidently true. But as for one the primary examples -- Reagan's campaign kick-off in Philadelphia, Mississippi, a fairly-obscure burg where three civil rights activists were murdered -- Bruce Bartlett makes a pretty convincing case that the speech's location wasn't the masterful prototype of the GOP's dog whistle politics that it's later come to represent, and was actually something of a campaign cock-up.
That said, when Reagan told a Southern audience that, "I believe in States' Rights," I think it's pretty clear what was signaled. Different language surely could've been found...
