Breakup of the New Deal Coalition, 1968. Carter was a deregulationist, nothing like the New Dealers.
True that Carter was the first to dabble in financial de regulation. That said, if you look at the electoral map in 1976, Carter's victory looked like that of a New Dealer (winning the South plus parts of the Rust Belt and parts of the Northeast). Nixon also governed far more moderately than he would've liked to, and in some ways governed to the left of the three Democratic Presidents (Carter, Clinton, Obama) that came since. I would say Reagan was the start of the 6th party system as he left the country far more conservative than he found it, something Nixon, despite his best efforts, was never able to achieve.
Carter's map was a fluke because he was a good 'ol boy, and southerners then tended to jump at the chance of electing a southerner. True that Reagan was more effective at implementing his brand of conservatism than Nixon, but Nixon had the southern strategy that characterizes the GOP of the 6th Party System and forever changed the GOP with the law and order platform. Note that he cut back on the Great Society and the space program. I think what happened here is that there was a "hiccup" in the realignment because of Watergate, but Democrats squandered their advantage and Reagan carried it on.
I feel like Carter sweeping the South (apart from VA and OK, which are atypical in the context of the region) was the last gasp of the "Solid South" as part of the Democratic electoral map. The realignment was definitely underway, but his nomination allowed the New Deal coalition (of which the South was a key part) to remain on life support for one last election.
That's what I was trying to get at with my response, but even in 1980 Reagan's closest states were in the south and I think even in 1984 some of Reagan's closest states were southern states.
As for the "hiccup" Anarcho-Statism mentioned, even without Watergate, I don't think the country would be as conservative as it got with Reagan. Sure Nixon gave us the law and order platform and the southern strategy, but it was Reagan that really made the religious right a force in American politics, it was Reagan (and to a lesser extent Carter) that ended Keynesian economics in America, ushering in economic neoliberalism, while Nixon was the one that said "we are all Keynesians now" and place (abet in a very half assed fashion) price and wage controls. Reagan also created disdain for poor people in this country in a way that Nixon never did. Hell, the Democratic party became more conservative (outside of some key social issues) for having Reagan, the Democrats got more liberal for having Nixon, and that was even before Watergate.
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