The only reason why Trump's victory in Utah was so narrow was because of McMullin's independent run. If McMullin didn't run, Trump would've won it by 60-70% like other Republican nominees.
Probably not the case; prior to McMullin entering the race, polling in Utah showed Gary Johnson with >20% of the vote. Trump might've done a couple points better, but it's difficult to see him eclipsing 50, and virtually impossible to see him eclipsing 55. Keep in mind that Trump was saved a little bit by how unpopular Bill Clinton was in Utah (he came in third here in 1992); polls during the primary season showed Sanders could conceivably have broken 40 here, and probably competed against Trump.
