I know that it has already been requested that a user is enabled to remove his close vote and it has been rejected here.
Still a have a case that is a bit more special. I had two tabs of stackoverflow opened and by mistake I marked this question as duplicate, while in fact I meant to post this in the other tab. Now not only that the question has a close vote that it shouldn't have but also there is a message above that it may already have an answer in another question that has nothing to do with the topic. I would like to request the ability to remove certain types of close votes and in particular duplicate. No matter how the user changes the question I doubt its duplicate state will change.
As you can see I have put a comment to indicate I have erroneously marked the question as duplicate but I believe the not above is far easier to see than my comment below.