There will be several states where McMillan doesn't get a single vote. Not much of threat that I can see.
The plan (and it's a good one) is to win Utah and Arizona, and possibly Idaho (17-21 EV). In a close election, this could send the election to the (new) House of Representatives, which would presumably guarantee a Hillary win even if she lost the popular vote and did not get 270 EV on election day.
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>> “There will be several states where McMillan doesn’t get a single vote.” <<
What brand of crystal ball are you using? (some are defective)