The more people you hire the more people have access to the votes for possible physical tampering.
At the end of the day there is no solution that will make all of our elections fraud-proof. Just audit every election from now on. Yes, it's a bit embarrassing that it's necessary, but sadly this is the world we live in now.
In how many universes has Lex been president? I remember as a kid there was one where he won the presidency and had the flash executed. Superman responds by going full authoritarian and executing him in return.