Trump won the 2016 election on a technicality.

[Zeitghost]

27. Not all States had binding public elections

To select their EC electors until I believe 1824.

The constitution does not require a public vote. Each state legislature has the power to decide how their electors will be selected. Have you read Article II?
https://constitution.congress.gov/constitution/article-2/#:~:text=The%20Person%20having%20the%20greatest,Ballot%20one%20of%20them%20for