That's bad logic. There are always dozens of candidates and activists trying lots of different tacts and strategies to get votes and drive opinions. One of those turns out to win in certain circumstances. That doesn't necessarily mean its author was a genius to have thought of it, just that they got lucky.

It's a darwinian thing. We don't credit the lobe finned fish for being such geniuses to have developed limbs which could hold them out of the water.

Are you willing to claim that intelligence isn't correlated with success at achieving one's goals? You can make that case, and certainly they don't always match up, but then what is intelligence?

I appreciate the evolutionary metaphor, but its also important to remember that candidates can (and do) change strategies and adapt to circumstances. Indeed, I would expect an intelligent candidate to try various different strategies throughout their campaign (and be better at it than their competition). Clinton and Trump both did. Clinton also had arguably much more help from very powerful allies, and had much more funding.

Also, developing limbs is not a choice; campaign strategy is.

How are you judging whether Trump is intelligent or not? Just because his words/actions seem irrational to you doesn't mean they are irrational. Scott Adams was pretty good at predicting Trump's behavior, so Trump's decision made sense to at least someone.