The last President elected without a college degree was Harry Truman, but Truman had served in the military and had served as Vice President AND as a war time President before he ran, and had distinguished himself in two of those three capacities (military and President: FDR had frozen out HST as VP).
Walker, however, left college after he lost an election. Or so his wiki says.
I see the Koch's backing Walker as, among many other things, part of the deliberate dumbing down of Americans.
The very odd thing about Harry Truman: Being President and fighting in World War I were the only two things he seems to have succeeded at in a big way. Go figure. He appears on most honest lists of Ten Best US Presidents. I don't see that in Walker's future, although the !@#$ does seem to be good at winning elections.
Truman had dreamed of going to the United States Military Academy at West Point, but he was refused an appointment because of poor eyesight.[15] He enlisted in the Missouri Army National Guard in 1905, serving until 1911 in a Kansas City-based artillery battery.[16] At his induction, his eyesight had been an unacceptable 20/50 in the right eye and 20/400 (past the standard for legal blindness) in the left.[17] The second time he took the test, he passed by secretly memorizing the eye chart.[18]
https://en.wikipedia.org/wiki/Harry_S._Truman
I heartily recommend reading the entire section in his wiki about his military career. And, while you're there, you may want to read the entire wiki. Very interesting, IMO.