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 my grandkids that I voted for him.' I won't do it."
Colorado, with its recent history of swinging between parties, was expected to be one of the main battlegrounds this presidential election, its sprawling Denver suburbs the front line of door-to-door political combat.
Instead, the intersection of mountain and plains has become something of an afterthought.
While recent polls suggest a tightening race, Republican and Democratic strategists alike agree that Colorado is Hillary Clinton's to lose, in good part because of voters like Nunnenkamp — women who might otherwise vote Republican but plan to stay home, vote independent or even cross party lines and support the Democratic nominee.
The gender gap, the difference in voting preferences between men and women, has been a constant of presidential politics since 1980. When President Clinton sought reelection in 1996, his support among women was 11 points higher than among men, a record.
Polls have shown Trump facing an even wider gender gap, with some showing a nearly 20-point difference — and that was before Monday night's debate when he repeatedly talked over Hillary Clinton, revived a feud with Rosie O'Donnell and was confronted with statements disparaging a former Miss Universe for gaining weight.
Dorian Hillegas, 34, voted twice for President Obama and, before that, Republican George W. Bush. She has no great affection for Clinton but plans to back the former secretary of State because "personally I think Trump's kind of a ticking time bomb."
"In times of chaos she's a little more composed and a little more professional than Donald Trump," the stay-at-home mom said as she paused between errands in this close-in Denver suburb, with her 2-year-old Maggie in tow. "He reminds me a lot of a 7th-grade bully. I can't support that."
Few states have undergone as rapid a political transformation as Colorado, which as recently as 2004 was written off by Democrats who saw no point competing for its nine electoral votes. At that point Republicans had carried the state in eight of the previous nine presidential contests.
Since then, Obama has won Colorado twice and now it is Republicans who, while not ready to give up, are having to make the case for Trump to fight on.
The rising influence of Latino voters, which has made states throughout the West more friendly to Democrats, accounts for part of the political change.
More significant has been Colorado's rapid population growth, driven by a thriving tech industry and the seduction of the state's outdoorsy lifestyle. More than 100,000 people moved here last year alone, the overwhelming majority settling in a ribbon of urban development skirting the Rocky Mountains.
The result has been horrendous traffic, a super-heated Denver housing market and a moderation of the state's traditional Western conservatism as the state absorbs a flood of younger, more left-leaning transplants.
In many ways, Colorado could not be a worse political fit for Trump.
In addition to having one of the youngest populations in the country, Colorado has one of the most highly educated; the real estate mogul and reality TV star has fared poorly among both groups.
Apart from some pockets of anxiety, there is also little of the economic dislocation and discontent that has fueled support for the GOP nominee elsewhere, especially in the industrial Rust Belt.
Thanks to a much more diversified economy, the latest downturn in the energy industry has caused nothing close to the devastation it wrought in the 1980s.
"We're happy in Colorado," said Jill Hanauer, a Democratic strategist in Denver. "And it's not because of marijuana," she added, referring to the state's booming legal-cannabis industry.
Colorado has also shifted politically in response to changes at the national level, as the Republican Party has grown older, whiter and more Southern in orientation.
Fairly or not, many see the party and its leaders as intolerant on social issues, such as abortion and same-sex marriage, and obtuse when it comes to the environment — which is deeply cherished here — by denying the reality of climate change.
That is particularly true among women voters, who not only tend to hold more moderate views than men but also care more, surveys show, about accepting others and getting along.
These days it takes a certain kind of Republican to prevail in a high-profile statewide race, said Dick Wadhams, a former state party chairman. The model, he suggested, was freshman Sen. Cory Gardner, who blended conservatism with a cheery, nonthreatening demeanor to eke out victory in 2014.
Trump, he said dryly, has been something less than an ideal candidate.
It is not so much his positions, which have proved changeable, but his sexist and uncouth statements that many women find objectionable.
"He's racist," said Rhonda Rispoli, a Denver bus driver. "Misogynistic, fascist, narcissistic.
"He's such a hothead, you could practically see the steam coming out of his ears and his nostrils," she said after Monday night's debate.
Rispoli, who gave her age as "early 50s," said she'll do anything to keep Trump out of the White House, including voting for Clinton — it would be only the second time in her life she voted for a Democrat in any election. (The first was former Denver Mayor Wellington Webb.)
"He doesn't have the Christian values I raised my kids to hold onto," said Rispoli, who cited the dynastic Bush family as a model of decorum. "I love those men."
Debbie Brown, a GOP strategist who specializes in women's issues, is herself no great fan of Trump.
But, she insisted, winning Colorado is not yet beyond his reach. Her advice was simple, if telling: "Don't call people names. Don't tell people they're ugly."
She called the debate a missed opportunity. "He seemed to be on the defensive and distracted from his target audience," she said, suggesting, "Trump should have been talking to suburban women" in a way that was "credible and solutions-oriented."
But for Helen Migchelbrink, it's already too late.
"I'm basically a conservative, but not a racist and not a sexist and not a xenophobe and all those things I think Trump is," said the 55-year-old Republican, an engineer in Fort Collins, who suggested the Manhattan business mogul "isn't even fit to serve as a small-town mayor."
She plans to vote for Clinton. And after that, "I'll probably register as an independent," Migchelbrink added, "just to show how disgusted I am."