[Cboldt]

-- where I vote here in Missouri we use a black marker to note our choices, then it gets scanned into a black box when we drop the paper into it. How do I know my vote isn't being switched right there? --

You don't. One of the ways some of these scanners can be hacked it to preprogram some votes into the memory card that holds and transfers the count. Preprogram negative votes for the loser, and an equal number of positive votes for the winner so the card shows "zero votes" when inserted to and checked by the scanner.

[DarthVader]

Yes but those paper votes can be hand recounted and would prove that something as you said took place.