I think that for voting to work well it has to be completely anonymous. So you can vote the way you want and nobody can prove you voted for the wrong guy.
Otherwise your Friendly Neighborhood Thug can drop by the day before the election and kindly ask everybody to vote B. He'll come back the day after the election to check the receipts and punish those who didn't vote the right way.
Using Wombat you can't convince someone ELSE that you voted the way he wanted you to vote, but you CAN convince yourself that your vote was counted!
Wombat also offer a verification mechanism, if the voter is unsatisfied that the system actually counts correctly. What it does is it encrypts the vote and then asks you if you want to verify that it was correct. If you do, it will print the decrypt key onto the ballot, rendering the ballot unvotable (because it can be decrypted), but you can then decrypt the encrypted text and see that it matches the plaintext. You don't even need to trust the machine itself :)
Otherwise your Friendly Neighborhood Thug can drop by the day before the election and kindly ask everybody to vote B. He'll come back the day after the election to check the receipts and punish those who didn't vote the right way.