Better yet: first, an anonymized database of all ballots is made publicly available on the Internet (this can even have IDs that let people check that their vote was recorded correctly). Alice, Bob, and Claire pick integers A, B, C much larger than the number of voters (N), and commit to hashes of those integers (this step can even be done before voting). Then they reveal A, B, and C, compute A+B+C mod N, and use that voter's ballot to determine the outcome of the election.