One way for agents to reach a joint decision is to vote over the
alternatives. In open, anonymous settings such as the Internet,
an agent can vote more than once without being detected.
A voting rule is false-name-proof if no agent ever benefits
from casting additional votes. Previous work has shown that
all false-name-proof voting rules are unresponsive to agents’
preferences. However, that work implicitly assumes that casting
additional votes is costless. In this paper, we consider
what happens if there is a cost to casting additional votes. We
characterize the optimal (most responsive) false-name-proofwith-
costs voting rule for 2 alternatives. In sharp contrast to
the costless setting, we prove that as the voting population
grows larger, the probability that this rule selects the majority
winner converges to 1. We also characterize the optimal
group false-name-proof rule for 2 alternatives, which is robust
to coalitions of agents sharing the costs of additional
votes. Unfortunately, the probability that this rule chooses
the majority winner as the voting population grows larger is
relatively low. We derive an analogous rule in a setting with 3
alternatives, and provide bounding results and computational
approaches for settings with 4 or more alternatives.