1976 was a poisoned chalice. Whoever won that election would’ve gotten screwed, given everything that happened. A buddy of mine predicted that if Carter got elected, Reagan could become President in the 80s and lead a new wave of neo-conservatism beyond Goldwater.
Here though, Ford won and the GOP just got wiped out after the mess of 1976. It also split the party between the “Rockefeller Republicans” and the so-called “Goldwater Republicans”. The former would come to dominate the GOP, especially after a members of the Green Party joined while the latter would join the Libretarian Party.
This also led to the Dems to push further left, which led to Mo Udall becoming President in the 1980s and having a supermajority to push universal single-payer healthcare in (known as Americare) among other benefits.
Udall and the leftier Dems willing to support the “Rockefeller Republicans” over the neo-conservatives got them both bipartisan brownie points and the favor returned when they showed more cooperation with their candidate, Jerry Brown, against Bill Clinton, head of the neo-liberal “New Democrats”, in 1992. Brown’s victory over Clinton solidified the rule of FDR’s influence over Clinton, and the neo-liberals left.
It did lead to the the Libretarian party becoming a serious contender alongside the Reform Party, the latter of whom won through Ross Perot. though by that point, they would not touch Americare, lest they suffer for it, though their tax policies led to a recession.
My guess is that if Carter won and the Dems taking the hit in 1976, Clinton’s New Democrats would dominate the weakened party by 1992 after 8-12 years of neoconservatism.