It appears to be IP based. I voted several days ago, tried again just now and at the top of the graph is the message:
You have already voted from that IP (216.254.53.52)
You'll notice that Anonymous Monk is capable of voting, which means it can't be purely login based.
--ChrisIn reply to (jcwren) Re: Casting One's Vote in the Boothe of Voting (twice)
by Anonymous Monk
in thread Casting One's Vote in the Boothe of Voting (twice)
by mischief
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