More important than lack of voter fraud is proving to the population a lack of voter fraud.
I'm sure you could even let every voter verify that their vote has been registered correctly.
Edit: But as a comment somewhere else in the tree noted ,,And if it could tell you that then a third party could force you to reveal that you voted "right" as agreed before.`` - I guess everything's trade-offs.
This. A voting system and it security must be understandable to the average people. You can not do that with electronic voting. (Even if electronic voting can be done securely.)