No doubt there are very many on the Democrat side who will attempt to vote more than once. Vote by mail and then show up in person and vote again! Who would stop them?
In most cases, it will show that you’ve already voted.
I was wating in line for early voting in texas when a woman came out saying they sent her home to get her mail in ballot. Somebody in the line said they don’t send you a ballot unless you request it. She claimed that they send a ballot to everyone over65. Wrong!