I think it would take these “Minor” parties being able to pull away a few “Major” party politicians to convert to a “minor” party. I don’t know if you noticed Senator Rand Paul endorsed the 2016 Libertarian Presidential Nominee, Gary Johnson is running as the Libertarian Nominee for the NM Senate Seat. That should be an interesting race, considering Johnson is currently polling at 2nd place (Below the Democrat, above the Republican). But there were a good number of Republican defections to the Libertarian Party in 2016 because of Trump’s craziness. They saw the damage he was doing/is doing to the party and got out while they could.