If you're transmitting information (even stochastic information) over a channel with noise (i.e. a random distortion of the data) there are good theorems and algorithms to recover the original variable from the distorted signal if you have a good model of the distortion. This is used ingeniously by IBM to protect privacy while still collecting customer information over the internet. Customer data is collected - but passed through a distorting filter. The filter safely eliminates any meaningful individual value of the original customer data, but the distribution of the original data can be recovered with good accuracy. Think a second about applying this to online voting. It would be theoretically sound, protect online voters from any possiblity of political pressure or abuse, but would be very hard to explain to the public.