I'd be interested. Verifying your vote will require either something you know or something you have, I would think. Either of which could be used by a malicious third party.
Look up zero knowledge proofs http://en.wikipedia.org/wiki/Zero-knowledge_proof
You'll have to go into it a little more given that the statement in question would look like "I, Richy_T voted for Satoshi Nakamoto(B)". That's the information that would need to be verified and the information that the third party would want.
Yes, I haven't looked into how to apply it exactly to this situation but when I read Oda.Krell's post and your reaction I thought it would be a high chance he meant something to do with zero knowledge proofs.