Sara, I had a problem a time back with the polls, but can't remember if it was the same error message or not.
Anyway, my problem was because of the pop-up blocker I had installed blocking the pop-up screens for the vote and results.
Whether this is the problem here, I have no idea, but it might be worth checking out and temporarily disabling any pop-up blocker you have installed. See if it helps.
LabRat