It has recently become impossible to close a question as a duplicate of another one if the duplicate does not have an answer. That does not imply that reposting the question is okay if a non-answered dupe is around, but the description fits the practical situation.
If that dupe was already closed, the new one can simply be closed on similar grounds.
As stated by Mat however, this particular case is an exception since the OP of the duplicate is the OP of the originally closed question. In which case the vote to close as a duplicate does not have the same requirements. The description does not entirely match for that scenario, but it might not be really worth updating it. Such duplicates should simply be deleted.