If that even happened I am sure not many will even consider using more than just one ballots.
All the studies conducted by both dems, GOP and more come to the same conclusion. There is no voter fraud in numbers that matter, anything found is factions of fractions, no individual messing with a vote of a few votes is gonna matter.
What matters is voter oppression, gerrymandering and all the other dirty tricks conducted. No which are worthy of proper democracies, that any honest politicians will sing so low is tragic.