4 way presidential race?

[Orser67]

This is the ideal scenario, new guy.  It would be wild and fun and Sanders would certainly win. 

No one would win a majority of EVs, the election would go to the House, and Cruz would win.

I certainly think this is the most likely scenario. I would say there are a few other possibilities:
1)Cruz finishes fourth in electoral votes, in which case the House can't choose him (see 1824),
2)Sanders doesn't compete in many of the red states (e.g. Mississippi), and Clinton wins the red states (due to the split GOP vote) and enough other states to take the election,
3)One of the campaigns falls apart, likely that of Sanders or Trump

[Orser67]

In the scenario below, Clinton wins all the Southern states in which Obama won at least 40% (except Texas) and Democratic-leaning and swing states that haven't voted (except Oregon) or that she won in the primary. Sanders wins all the Democratic-leaning and swing states that he won in the primary. Trump and Cruz take the remaining Republican-leaning states in primaries that they won (as well as nearby states).

Clinton gets 323 EVs.