> I think any software that has the potential to influence election outcomes should be provably correct (the whole stack), open source and probably have been out in the wild for years before getting used in a real election.
Let's remember that even when paper ballots are used, the counting is done electronically. It's not something people often take time to consider.
When the ballot boxes are emptied, the ballots are scanned with scanners, and the results put into some sort of software to be processed further. This is how it's been done in Norway for many years, and we're only 5 million people here, so I can't imagine other countries doing it any differently.
Norway introduced a new voting system a few years ago, which also included Internet voting, but that has later been put on hold, as it was blocked by political reasons. The entire system was open source (you could read the code, but not allowed to use it), but I don't think it has been released since then, and I'm not sure what the plans were. Fun fact, the settlement algorithm that ranks the candidates is a Postgres stored procedure (http://goo.gl/PPMipF).
There is already a lot of places where there is software that can influence election outcomes, and it's definitely not proved to be correct. Given how trojans have been found everywhere in the recent years, I'd not be surprised if some countries election software stack has been compromised.