Not always -- it varies on a state-by-state level. I live in NJ, where you can do this. However, it only works because absentee/mail-in balloting is held unti

Not always -- it varies on a state-by-state level. I live in NJ, where you can do this. However, it only works because absentee/mail-in balloting is held until after election day, and in some cases are only counted if the election is within the number of absentee ballots, and an in-person vote will trigger them to manually throw out the mail-in ballot.