I think you need to start with proposing how a person could fraudulently vote.

If you show up to the polling place, you need to list the name and address of a registered voter in that district. How do you know this information?

If you use a relative or acquaintance whose name and address you know they're registered at, when they show up to vote it will be noted that they have already voted. They can then put in their preliminary ballot, and presumably their signature will more closely match the fraudulent one and the real one will be counted.

There are enough basic hurdles to this that I don't see how it can even be done at scale.

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Muromec an hour ago | parent [-]

I always wondered (Clearly Not North America) How does one get on a list anyways? I would imagine getting on a list fraudlently leaves paper trail and this would have been discovered in 5 minutes retroactively, but I'm still curious.

	▲	lobf an hour ago \| parent [-]
		When you register to vote, you give your address as well as proof of eligibility to vote. That address is used to assign you a polling place, and also as an additional piece of data needed in order to filter out fakers. Your voting eligibility is checked before being added to the list, which also mitigates fakers. If you're trying to register in someone else's name, you have to pray that they don't register themselves or show up to the polls to vote. That's a gamble which prevents systematic individual voter fraud.