I don't think so, because clones are always a hard thing to prevent. Anyway, there are techniques which allow us to catch the more careless, by watching users that have the same IP at the same time. A tool to see where the user voted would be great, so you could compare if the votes went all to the same user (the main account). :)
Unfortunately I don't think any of these techniques are yet implemented in Q2A, but I think it's possible to create a plugin with such function. :)