I'm not sure what skills you consider necessary to win both a contested primary election and a national election, but I'd consider many of them intellectual skills and the competition to be of a high level.
Savvy, but not intelligent. His brain is heavily optimized to be skilled at the particular American environment of celebrity worship, mixed with perceived business success. He is able to capitalize right now on that, but I'm not sure there is an adaptive intelligence in there.
Money and name recognition. If it wasn't for the TV show 'Apprentice', it is doubtful that people would have known who he was. That show is what established his (completely fabricated) reputation as a successful, skillful businessman, and he was able to ride that wave all the way to the White House.
> Most people in America didn't know who Trump was before that show aired.
Maybe most people who were quite young when it aired; Trump was a constant media presence from something like the late 1970s well into the 1990s, and sort of a pop culture touchstone for conspicuous excess as well as having a reputation as a successful NYC developer and prolific womanizer.
