That already happened. The Kansas Dem nominee and Indy were splitting votes, but the Indy was polling better and he's able to self-fund. They convinced the Dem to drop out. The Kansas SOS (a Repub) tried to keep the Dem on the ballot, after his office said the Dem did what was needed to get off the ballot.
They went to the courts, and the courts decided the Dem could drop off the ballot. So the Kansas SOS is now it hot water for a highly partisan move, and is up for re-election.
Like I said earlier though, I'll believe that deep red Kansas kicks out incumbent Repubs when I see it.