Looked it over. The main reason why the proposed solution would help reduce fraud is that each vote is authenticated. But that's not how our voting system works. People can show up in person and not show id and vote. Huge number of absentee ballots can be mailed in and they have not been authenticated. The election workers can throw out votes, they can change votes. To go the blockchain route defined in the link above, we'd have to go totally digital and have a national id, potentially with cryptographic keys, for everyone wanting to vote.