A third party is literally insane - NO third party has won, EVER, unless you count the Republicans themselves after the Whigs imploded (but almost all Whigs became Republicans, so it was more a re-branding than a genuinely new party).
If a massively popular ex-President couldn’t win with a third party (T.R. as a Bull Moose), then NO ONE can or ever will...and there’s no one of 1/10 of his stature to run, on top of everything else.
I can only surmise that anyone who genuinely supports a third party in these circumstances is a Hillary supporter.
Of course, if Bernie Sanders wants to run as a third party candidate, I’ll support that. Let the OTHER side implode by dividing itself.
". . . supports a third party in these circumstances is a Hillary supporter."
Or believes God is telling them what to do and promising them victory.
Which can't be ruled out when it comes to Cruz or the billionaire queers giving him most of his money.