One of the theories on what's happening behind Trump's recent bump is that conservative Johnson supporters have been reluctantly walking back to Trump. In line with that, it makes some sense that McMullin would've also gotten some sort of a boost as Johnson fades. This seems to not have happened and his chances in Utah have probably tanked. He's basically down to a 10% chance for winning Utah.
Rasmussen/Pulse Opinion Research (OCT. 29-31) (538: C+)
750 LV
Clinton 31%
Trump 42%
Johnson 3%
McMullin 21%
SurveyMonkey (OCT. 27-NOV. 2) (538: C-)
1,247 LV
Clinton 30%
Trump 33%
Johnson 8%
McMullin 25%
Monmouth University (OCT. 30-NOV. 2) (538: A+)
402 LV
Clinton 31%
Trump 37%
Johnson 4%
McMullin 24%
Emerson College (OCT. 31-NOV. 2) (538: B)
1,000 LV
Clinton 20%
Trump 40%
Johnson 3%
McMullin 28%
Still no public polling data in states with sizable Mormon minority populations like Idaho.