It's possible via homomorphic encryption, i.e. a way to manipulate cyphertext to make some mathematical operations like sums/products or logical comparisons wit

It's possible via homomorphic encryption, i.e. a way to manipulate cyphertext to make some mathematical operations like sums/products or logical comparisons without revealing the actual secrets. For example, it's possible to compare two encryptions of two numbers and get an encryption of their sum or to know which one is larger without knowing either. However one drawback of such a voting system would be an inability to get actual vote tallies, only an ordering of the candidates. There is an older google talk about this delving into more detail. https://www.youtube.com/watch?v=ZDnShu5V99s https://www.youtube.com/watch?v=ZDnShu5V99s