That number can be checked against an election tally system to ensure that the vote was cast as specified.
This is more down a to a poor explanation of the system than a risk within Helios itself.
The Python Software Foundation recently switched to Helios. I don't think it's perfect as a system but it goes further to dealing with the potential issues than any other system I've seen.
I'm a huge fan of paper-based systems for national elections but I think that the Estonians have raised several credible reasons for some potential problems.
As for the US: fraud and system failure would be less of a worry if more people could be bothered to vote in the first place. Turnout at elections in the US is routinely abysmal.
Biting the hand that feeds IT
