My family will go for a third party Conservative candidate (hopefully Sarah!) before voting for a Republican establishment pick like Romney, McCain, Gingrich, or a host of others. We would rather see another term of Obama hamstrung by a conservative congress and senate than another globalist, anti-constitution president like any of the Bushes.
I can't see Sarah being defeated for the GOP nomination and then running on a third-party ticket.
That is a dishonorable move and Sarah is not dishonorable.