Rep. Morris Udall (D-AZ)/Sen. Adlai E. Stevenson III (D-IL) 294 EVPres. Gerald R. Ford (R-MI)/Sen. Robert Dole (D-KS) 244 EVFord would have been a prohibitive favorite in the South in such an election as this. He'd have swept all of the Southern states, not as big as when McGovern ran, but he'd have taken 60% of the vote in the South overall.
On the other hand, Udall would have carried California. Carter lost California in no small measure because of moderate Republicans and some Democrats in California who saw Carter as the more conservative candidate (certainly on social issues).
Udall would also not have had to endure the "wishy-washy" narrative Carter had to endure because of his (necessary) attempts to appear conservative in the South and at least a moderate in the Northeast and industrial Midwest. For this reason, I think Udall would have carried Maine, Connecticut, and even New Jersey, states with lots of union members and some anti-Southern bias that impacted Carter against the moderately conservative Ford. I think Udall would have held West Virginia as Michael Dukakis did in 1988 (thanks to the UMW). I also think Udall would have carried Illinois with Stevenson as his running mate.
The critical states for Udall would have been Ohio, Missouri, and Iowa. I gave Iowa to Udall because it was one of McGovern's better than average states. I gave Missouri to Udall because it was far less Republican than it is now, and it also had a large base of union members. Ohio would have been the tough call, as Ohio was the most Republican industrial state in the Midwest, save for Indiana which regularly went Republican. Here Udall would have benefitted from the sluggish economy and resentment toward Nixon for Watergate. Iowa was also a dovish state and it carried for Ford in 1976 in part because Carter was considered a more hawkish Democrat than the Democratic norm.
I'm not sure what the map would have been against a Ford-Reagan ticket. I am not certain that such a ticket would have been frought with internal strife, but it would likely have carried California. On the other hand. Would that have been enough to overcome the Watergate issue and the economy? That's an interesting question. Having been politically active at that time, I am not at all sure as to how that would have played out.