No.
That Carter won was no suprise, but Republicans could have had their standard victory if Reagan had been the nominee.
The political base of Carter and Reagan where almost identical.
Reagan would have denied Carter his southern sweep while also keeping the west.
1980 could have happened in 1976.
Any Reagan win in 76 would've been close given that 1976 was a very Democratic year, and Carter likely would've carried the states in the midwest that Ford only narrowly carried in a matchup with Reagan, softening the blow (or at least somewhat softening) of any loses in the south, which I doubt would've been many if any as keep in mind also that even in 1980 Carter only narrowly lost the south. In a much more favorable environment, Carter still would've likely held most of the south. Also keep in mind too that most of the general electorate (and even some Republicans) still saw Reagan as a fringe wing nut in 1976 and that would've hurt him against moderate southerner Carter.
I'd also add that even if Reagan were to narrowly win in 1976, it wouldn't have been 1980 and Reagan would've likely been crushed in 1980 much like Carter was as I think Reagan would've been even less equipped than Carter at mitigating the malaise of the late 70s.
