Carrying out voter fraud is pointless unless you can do it without being detected. If you flood one precinct with enough votes to swing an entire election it be

Carrying out voter fraud is pointless unless you can do it without being detected. If you flood one precinct with enough votes to swing an entire election it becomes very obvious that something fishy went on there. The only way to rig the election with voter fraud and get away with it is exactly the same - by spreading your fraudulent votes thinly so that no one area is too suspicious.