That and “popular” doesn’t mean “competant.” Reagan was a moron. Even his own people pretty much said so. Nice guy, but a moron. (And from what I’ve read, he was pretty much a figurehead).
ETA: Also, Ike and Teddy Roosevelt were pretty popular in their days as well.
Point taken — your revised question should stand. 
I've no interest in bashing R.Reagan (despite having a lot to do with changing the Party of Lincoln), but yes, others present strong claims for popularity. Post WWII Ike had "rock star" appeal though his presidential tenure managed to tarnish the five stars.