I could see a 4way. Trump will go independent alone, sanders will go independent after being forced out just out of spite to get back at the dnc, and whichever theocrat the gop pics will be the also ran.
The vote splitting will be amazing with a little over a quater each for everyone but the gop candidate, ending with no real winner of merit at 28% or some such.
I really think there will be something very unusual happen after the bulk of the delegates are done but all the states havent voted. Some revelation on anyone's part be it birther for rubio cruz, business for trump, or clintons dirty laundry,one will be on the brink and drop out.
I really think none of the big 5 will be potus. SOMETHING is going to happen. Some dark horse, or "incident". Something will make the election be postponed say. Like a death.