They would probably only need to strip a few thousand voters in the swing states to accomplish their purpose.
Freegards
If they run.
If you're serious, you assume Trump supporters could be swayed, and Bernie/dems would not.
My napkin scratches show the opposite is more likely. Zero Trump supporters would bail, resulting with as many (or more with converts) from '16. 63 million. Bernie's 20-30% don't budge either, but the middle might....even more moving right leaving scraps of 15-20 % max for an indy ticket like this.
Are blue-color workers, farmers in those midwest swing states going for Romney/Bloomberg ? No way. Bloomberg has just insulted the hell out of them, for starters, and Romney's elitism and complete lack of empathy for them won't sell either.