Think Teddy Roosevelt in 1912. Of course, his deciding his former protege Taft and the Republican party had strayed from what he believed in, turned things into a three-way race. That became a two-way race between Wilson and Roosevelt, and with Taft and the Republican party siphoning off enough votes, Wilson got the win.
Believe me, I would love for a legitimate third or even fourth party to come around and force the GOP back to its roots, but I'm not the only one to say that I'd rather vote Republican than see a democrat win, even if it's for a RINO.
If you can find your Teddy Roosevelt, you've got a shot. Democrats bitched about Nader, but they conventiently forget that a few hundred thousand registered democrats voted for Bush in Florida.
It's not about a candidate. It's not about any particular election.
It's about a new party with a new focus. It's not about forcing any party back into the fold.