i have a theory of a scenario where this could happen, sasuke defeats naruto in their final battle and realizes that they were friends all along, as naruto is dying he asks sasuke to protect the leaf sasuke abides by his best friends dying wish and bang uchiha hokage, now just because i can see sasuke as hokage doesnt mean i think it will happen, but I suppose it is possible
IF sasuke really crushes the leaf and fulfills his revenge,
IF he cools down a bit after destroying the leaf and
IF he and madara each get an uchiha-family big enough to fill the city, it could be possible.
in theory he's intelligent enough, he very much cares for his clan and he's not like naruto who will risk to sacrifice everything for every no-name-character. he has his own head and isnt as gullible and careless as naruto.
the problem are the three ifs. i highly doubt that any of them will come true.
I can't really see Sasuke as a Hokage, they are supposed to be good leaders, and the trend sees them as rather nice, with the exception of Danzo. Kakashi almost became hokage, and at least he has a sense of humor. Gaara even changed to be a lot nicer and happier. But Sasuke kinda went off the deep end.
Not unless he single-handedly defeats madara and saves the ninja world. I don't think that anyone would feel safe with someone as unstabble and evil as him being the hokage.