Emerson College found that McMullin was strongest among younger voters, capturing 36 percent among those 18 to 34, while Trump and Clinton received 22 percent each. Trump beats McMullin, 35 percent to 24 percent, among those who are 55 and older.
McMullin claimed 35 percent of the Republican vote, while Trump took 44 percent. Independents favored McMullin (35 percent) and Clinton (31 percent) over Trump (10 percent).
McMullin has surged in the days since the "Access Hollywood" video emerged showing Trump caught on a hot mic bragging about groping women. Since then, Trump's numbers have fallen, McMullin has surged and Clinton has remained steady. CNN, Fox News and NBC all have now declared Utah a toss-up.
That video was the final straw for freshman state Sen. Lincoln Fillmore, R-South Jordan.
"The party nominee has abandoned the principles of the party," he said. "I think that is very clear."
Fillmore gathered a group of Utah Republicans to endorse McMullin. That included state Sens. Howard Stephenson, Curt Bramble and Daniel Thatcher, along with state Reps. Paul Ray, Justin Fawson and Fred Cox.
Fillmore said McMullin had the "character" to be president, and he likes McMullin's diverse experience, which includes 10 years with the CIA, a stint with Goldman Sachs and a few years as a Republican policy aide at the U.S. House.
Fillmore believes McMullin is a big upgrade over Trump and Clinton; still, the independent wouldn't have been his first choice.
"Evan is the beneficiary of very weak competition," said Fillmore, who supported Florida Sen. Marco Rubio and businesswoman Carly Fiorina in the Republican primary. "If Evan had been in that process, I still would have been a Marco Rubio and Carly Fiorina supporter. But given the state of who his opponents are, Evan clears the bar even though, admittedly, that bar is very low."
If McMullin were to win in Utah, he'd be the first third-party candidate to win any U.S. electoral votes since 1968, when Alabama Gov. George Wallace won five Southern states as a candidate for the American Independent Party. Utah has supported the Republican nominee in every presidential race since 1964.
For McMullin to have a chance to win the presidency, he'd not only have to carry Utah, but Trump and Clinton also would have to be in such a tight race that neither received the needed 270 electoral votes. In that rare event, the U.S. House would pick the president.
McMullin, a realist, says that scenario is unlikely with Clinton polling so well in states where Republicans have traditionally won, such as Georgia and Arizona.
"All of the Electoral College projections say [Trump] is going to lose badly," he said. "So we can dispense with the idea that a vote for me is a vote for Hillary Clinton. That is not the case."
If the White House is out of reach, McMullin said Utah voters should support him "to take a stand on our principles" and after the election, try to create a new conservative movement. With that in mind, he plans to spend the bulk of his time between now and Nov. 8 in Utah, Idaho, Wyoming and Colorado, with stops in Iowa, Virginia and Minnesota. McMullin is on the ballot in 11 states, having entered the race as an anti-Trump candidate in August.