Earlier quoted context omitted.
I think you could do some secure voting software if all your citizens had a secure two factor signature and you used block chain. I'm not sure why you would do it in a non-corrupt country though.
And how do you prove that all of those citizens exist? We have a secure, provable, relatively cheap method right now: Paper ballots and public observers at elections. Compared to the stakes the cost is peanuts.
The fact that virtually anyone both capable and eligible to vote is also capable of understanding the voting process, as well as what kinds of physical acts are signs of fraud means that many more people can evaluate the process, and determine - even just by looking - whether something fishy is going on at their voting station.
Your average voter will be easily convinced that he "doesn't know enough to judge" whether something is fishy with his voting machine, even if something seems to be clearly malfunctioning; "oh don't worry sir, the print out might be wrong, but your vote was definitely counted correctly internally".
The rise of any form of electronic voting is really troubling - and don't even get started on anonymity concerns...