why didn't ike do better in the deep south?
adlai was a liberal intellectual. Ike was a war hero from modest, non-east coast roots.
It wasn’t the first time Southerners happily voted for a liberal intellectual over a Northern (moderately) conservative Republican.
It was pretty much the last time however. And Ike made it WAY closer in the South than Dewey, Willkie, Landon, and most Republicans before them. He won Texas, Oklahoma, Tennessee, Virginia, and Florida twice. He came very close to winning the Carolinas. As noted, he flipped Louisiana, Kentucky, and West Virginia the second time. He even made states like Arkansas and Alabama close compared to previous margins for Republicans there.
If anything, Ike’s gains in the South are too often underlooked; they were a sign of things to come and proof that the shift of the region from solidly Democratic territory was already well underway by that point (largely in response to the increasing social liberalism of FDR, Truman, and Stevenson). And that Southerners could and would vote Republican under the right circumstances, not just protest vote for Dixiecrats. Nixon and Goldwater would just solidify this.
In fact, Ike campaigned in the South against the advice of his campaign which wanted to write it off. Turns out he had the right instincts.