If Bernie tried to pull a 3rd party run in any circumstance, he would not be winning any states, he would not be polling double digits, and he would guarantee himself a loss to a primary challenge in 2018. This is getting really unrealistic.
I disagree. Bernie would attract Ross Perot level support as a 3rd party candidate given his overall popularity and his crossover appeal. The only unrealistic bit is that Bernie Sanders would never run as a 3rd party
Reason he is doing this is unlike in OTL Hillary has no chance of winning, so his belief is if Hillary loses by a massive landslide, instead of like a 1996 type margin in the electoral college it would force the Democratic Party to take the populist left more seriously.
Given that Bernie Sanders supported Walter Mondale in 1984 when he trailed the entire election, on paper, that wouldn't mesh with Bernie's record, though to be fair, he wasn't in the position to run 3rd party back then.
