So let’s say I post a question and it doesn’t get answered, drifting into oblivion. Is there a way to pump some new life into it, or do I have to delete it and post it again?
From the help center:
What should I do if no one answers my question?
First, make sure you’ve asked a good question. To get better answers, you may need to put additional effort into your question. Edit your question to provide status and progress updates. Document your own continued efforts to answer your question. This will naturally bump your question to the homepage and get more people interested in it.
If, despite your best efforts, you feel questions aren’t getting good answers, you can help by offering a bounty on any question more than two days old.
There are also some suggestions on the How do I get attention for one of my own questions without a good answer? FAQ entry, namely editing with updates as you've continued to work on it, posting a link in SE chat rooms, and posting a link on social networks.