Chelsea Nunnenkamp is the kind of party loyalist who bleeds Republican red.
She started walking precincts and stuffing envelopes for GOP candidates at age 15. During high school, she kept a poster of Ronald Reagan above her bed.
But come November, for the first time ever, she may vote for a third-party presidential candidate or, possibly, skip that line on her ballot altogether. She is terrified, she said, by Donald Trump and his egocentric campaign.
"I just feel with such strong conviction that I do not want to be associated with that," said Nunnenkamp, 28, who works in Denver's oil and gas industry. "I joke with my friends, 'I don't want to tell...