Consider the revisions for this question, which I looked at following
someone crying over lost rep another meta question here.
As far as I can tell, a sum total of 9 people though it bad enough to close/delete, but only 5 were required to replenish its mana. That's just an observation though.
The question is - why does deleting require 5 votes and un-deleting only 3?
An answer to this question probably answers the undelete vote count part of this question. But this question goes a bit deeper, and discusses the seemingly unmatched unique number of persons between delete and undelete.
Is there a better solution to make sure everyone's vote weighs the same as the next StackOverflower's?