I have had political experience (union politics, as dirty as they get) in overthrowing a corrupt regime. You simply don't allow the opponents to remain in place. I've seen the fizzle of a third party in Ross Perot's campaign, by which we got Bill Clinton. People like to point to the GOP as having an origin as a third party, but that was in a context where (1) abolition of slavery was an existential issue, and (2) the Whigs were already in decline. Personally, I dislike abandoning the party of abolition to the RINOs. Abolition of slavery, be it by modern means, is our issue of the day.