In the 10K tools for stackoverflow, there is a question that was migrated. Yet, it sits there, using a space, without a delete link, on the list of things with pending delete votes.
That single delete vote was cast a few days after the question was initially closed as "off-topic". You are correct that the vote will hang around without moderator intervention.
What should have occurred is that upon question reopening, pending delete votes are removed - we'll change reopening to work this way.