During last night's debate, Andrew Sullivan wrote: "It could well be that this could come down to Romney-Gingrich-Paul. That trio is the end of Republican fusionism."
Maybe. Some of us have been dreaming of that for years. The time has long passed for people who broadly define themselves as "socially liberal but fiscally conservative" (20-30% of the American people, depending on who you talk to) to realize they have no natural home in either major party.
If Ron Paul is really playing the long game (and I think he is), this is what I'd advise him to do:
Stay in this thing to the convention. Get ~20% of the delegates. In the meantime, (quietly) lobby for Gary Johnson to get the LP nomination (I know you know people.) The LP convention is months before the GOP's, so you'll know exactly where it stands by the time it matters. Assuming that goes well, on the first day of the GOP convention, hold a press conference in which you 1) release your delegates, 2) quit the GOP, and 3) unequivocally endorse Gary Johnson for President.
Johnson won't win of course, but a strong spoiler will either re-orient the GOP (much more likely), or destroy it. And one of those things needs to happen.