Not surprised to see a general pattern among the group.
I have to agree with Lincoln as well (He didn't see to the end, but he hung in there), Reagan for reasons stated (communism, military, etc) and I'm surprised to see Nixon only once (China, Vietnam, seemed to me to be a "regular" person - flawed). That by no means is to say every other President is perfect...
Personal Fave: GW Bush - the reason I signed. "Moral clarity," as Hannity says.
P.S. Why hasn't Carter received a mention..?