Assume Sanders and Trump both run successful insurgency candidacies, but fall just short at the convention. Perhaps Hillary relies on super-delegates to overturn a delegate count favorable to Sanders. For whatever reason, both Sanders and Trump decide to launch independent candidacies. They manage to get on the ballot in all 50 states. What does this election look like?
I would expect Hillary and Sanders to split the black vote about 60-40, and the Hispanic vote to be split about in thirds by them and Jeb. Sanders to max out the liberal activist base, Trump to max out the low-information/poor white voter. Hillary and Jeb vying for the remaining whites. Draw a map with this scenario.
Here's my map, for fun.
214 Hillary
209 Bush
58 Sanders
57 Trump
I don't know why you would give TN/KY/WV/SC to Trump: the South is extremely inhospitable to third party candidates in general - Perot, Anderson, Nader, etc. (Wallace's "I'm a Democrat but I hate black people as much as you do" candidacy doesn't really count.) He would probably overperform in places like Montana and Alaska, though.
I don't know why all of you think RI would vote for Sanders over Hillary.
Yeah, Rhode Island is the sort of place that would vote for Dick Cheney for president if he were the Democratic candidate.
Rhode Island is just such an anomaly. Demographically, it looks like it should be Catholic Oklahoma, but Democrats show no signs of losing support there.