It's gonna happen, whether it swings to Hillary or one of the 3rd parties. Utah is demographically a Mormon (Latter-day Saint) majority, with a little over 50% of the population claiming to be members. Mormon remnants and culture tend to lean to a more conservative political viewpoint, which is why, historically, Utah has voted for the Republican Party despite many non-Mormons holding liberal views. However, the positions and character of Donald Trump have really ruffled a lot of Mormon voters. I would cite news sources if I weren't on mobile, but both the Deseret News and the Salt Lake Tribune have written about the Mormon's disdain for Trump, in addition to speaking out against him. I think it's highly likely that Trump will not win Utah simply because he does not have the support of the majority of the voters. Disclosure: I am a Utahn and a Mormon.