I am considering reposting a question that has gone "stale" -- that is, it is no longer new and therefore not garnering any attention. It also has content that is no longer relevant: it was a jQuery question before and now it is a Regex question, and it should indicate this new category.
What will happen if I do? Would I be banned for that? If not, is there a protocol to follow, to ensure it is not seen as a duplicate or otherwise unwanted?
Assuming anyone notices it (which is rather likely) it will be closed as a duplicate of your previous post. It's also very likely to get lots of downvotes and not to be answered as soon as people notice that it's a repost.
Having a noticeable percentage of your questions closed and/or downvoted contributes towards a question ban, so doing this repeatedly can easily get you banned from asking questions entirely.
See How do I get attention for old, unanswered questions? for how to properly get attention to your existing question, instead of reposting.
