When you run an election you're supposed to basically track down a thousand random voters to make sure they actually exist and are legitimate. This is a really easy way to prevent most fraud. The number can vary really, depends how close the results are but when they're as close as they have been then you are looking to do at least around thousand or so.

When you find a bunch of these voters don't exist then that's a big problem. 20% is so high though I have to wonder if something else is going on. Might not be but fraud on that scale is quite shocking. You'd usually do it when things are tight because you only have to so a few percent or so. In certain races the impetus might go the other way around. The worse the chances the more you have to cheat.

When you run an election you're supposed to basically track down a thousand random voters to make sure they actually exist and are legitimate. This is a really easy way to prevent most fraud. The number can vary really, depends how close the results are but when they're as close as they have been then you are looking to do at least around thousand or so.

When you find a bunch of these voters don't exist then that's a big problem. 20% is so high though I have to wonder if something else is going on. Might not be but fraud on that scale is quite shocking.