The only reason that the mormons voted for Reagan in 1980 is because they were mad at Carter and the Democrats...
That 1978 thingy about the blacks...
carter put pressure on them to change their racist doctrine...
or lose their tax status...
Nope. Since statehood Utah had been pretty much straight line Republican. 1980 was not exceptional.
Since statehood Tennessee had been pretty much straight line Democrat 1980 was exceptional. By less than half a percent.
In the crucial 1976 Michigan primary Carter had Coleman Young accuse Mo Udall of racism because he was Mormon even though Udall had not attended LDS services for years in protest of the doctrine. Carter won by around 1% and went on to win the Presidency. You could have had a Mormon President!
After that there was enormous pressure by the Udalls and Romneys and from within Utah to revisit doctrine. That is what begat the change.