I do not support him but he has a 70% or so approval rating at home
If your 70% number is correct and if I remember right AZ is split about 50-50 Republican/democrat. So that means with the 50% democrat approval he has he only has 20% Republican approval.
....maybe true in Ariz....and among far leaning conservatives the same....but his numbers are much higher in mainstream.....they just are.....
Redo your algebra. Using your figures, he has 90% Republican support in Arizona.