GOLDEN, Colo. – The Rev. Brian Young has been preaching about tolerance ever since two conservative families left his evangelical church four years ago, furious about a Barack Obama bumper sticker in the parking lot.

Conflict over politics has lessened in his mountain congregation, he said, but not in the Denver suburb of Golden below.

"It's even worse out there," Young said. "Lines being drawn and sharp words. … I have encouraged people to turn off their radios and open their Bibles."

Less than three weeks before Election Day, Jefferson County is once again among the most competitive counties in a battleground state. It's a microcosm of the Mountain West, where changing demographics have opened once solidly Republican states to Democrats but a struggling economy could slam the door on the Democratic gains.

The county's middle- and working-class suburbs are saturated by television advertisements, telephone calls and direct appeals by Obama and Mitt Romney, the Republican nominee for president.

At the Ace-Hi Tavern in downtown Golden, a bartender discourages political conversations for fear of a disturbance. At a cafe across town, even a Republican who considers himself a "hard-core son of a gun" typically keeps his counter talk to fishing.

"I'll be glad when it's over," said Dwayne Nelson, 68, who retired in 2000 from his job as a pipefitter and welder at the Coors brewery that remains a major presence in town.

The intensity of the presidential campaign is an adjustment for the people of Golden and for a state that was once so conservative it wasn't competitive.

Republican presidential candidates carried Colorado in nine of 10 elections before Obama won in 2008, aided by an expanding Latino population and by young, college-educated people moving to Colorado from California and other Democratic-leaning states.

The electorate is now about evenly divided – one-third each Republican, Democratic and unaffiliated.

"The bottom line," said Peter Hanson, a political science professor at the University of Denver, "is we're importing Democrats."

Marjorie Sloan, the Democratic mayor of Golden, describes the changing demographic in generational terms, in which "the Old West rancher types are no longer the majority." Some people in this city of about 20,000 are unhappy about it.

"This place was better 30 years ago," Dave Calwil, a 57-year-old Republican, said over coffee at J.C.'s Cafe. "It was more small-town."

Many unaffiliated in county

Jefferson County, along the Front Range of the Rocky Mountains, is significant to Obama and Romney because of its size – the county is home to more than 400,000 of the state's 3.6 million voters – and because of its large number of unaffiliated voters. Those voters tend to be relatively young and socially moderate, but with a "libertarian streak," Hanson said.

They are also more persuadable than Democrats or Republicans so late in the election. The Obama and Romney campaigns are both "hitting the ground game hard" to turn them out to vote, said Kyle Saunders, a political science professor at Colorado State University.

On a recent afternoon in Jefferson County, Obama volunteers prepared canvassing materials, while Romney supporters gathered at campaign headquarters to eat chili and write postcards to undecided female voters.

"I'm appalled at the current administration," said Judy Merkel, 67, a Romney volunteer.

Suburban women helped Obama carry Colorado in 2008, and they are a coveted group once again. Suzy McKee and Terre Deegan-Young, 63 and 64, respectively, said they receive as many as six or seven campaign calls each day at their homes.

McKee, a Democrat, and Deegan-Young, an unaffiliated voter, both support Obama, but the two friends are discouraged by the negativity of the campaign and by its cost. Partisan conflict in Washington appears to them to be intractable, and Deegan-Young said it "starts giving you a feeling of helplessness."

Obama won Colorado by nine percentage points in 2008. But a sputtering economy has hurt his prospects this year, and even supporters acknowledge the campaign lacks much of the enthusiasm it exuded four years ago.

That year, Sylvana Strong was so happy about Obama's election she cried.

Strong, who is 18 and a freshman at the University of Northern Colorado, still lined up on a chilly morning in Greeley recently to hear Vice President Joe Biden speak, but she and her boyfriend, Henry Thomas, 20, had to remind each other that change "takes time," perhaps more than four years.

"I just thought he was going to do so much more for women's rights, for health care, for the economy," Strong said.

Able to vote for the first time this year, she said her ballot will be as much a repudiation of Romney as it is a vote for Obama.

Thomas nodded. The campaign, he said, "was a lot flashier in 2008."

Economy is top issue

The unemployment rate in Colorado remains above 8 percent, marginally higher than the national average, and like elsewhere the economy is the issue at the top of voters' minds.

Romney is seeking to capitalize on the disappointment. As Biden spoke in Greeley, the Romney campaign set up a tractor in a park across town and attached to it a banner that suggested the middle class is "buried in debt."

The imagery resonates in rural reaches of the state, where voters are as likely to measure the state of the economy by the price of fertilizer as by the number of housing starts.

"Before Obama took office, basically, fertilizer was running around $250, $300 a ton," said Tom Hulet, who farms hay and has a refrigeration business in Montrose County, on the state's western side. "Now it's anywhere from $800 to $1,200."

The 56-year-old Republican said Obama is a "Marxist," though he is unsure if he will vote for Romney or write in a vote for Texas Rep. Ron Paul.

There are signs in Golden that the economy is improving. Calwil, who frames and trims new houses, said work has picked up since the beginning of the year. Tyler Johnson, a clerk at the nearby Days Inn, is happy not to be working at Burger King anymore.

Johnson, 22, is an unaffiliated voter who makes about $12,000 a year and lives at the hotel. Sub-$4 gas and fewer vacancies at a nearby mall are to him "an indication that things are getting better somewhere." He will vote for Obama.

"Romney, he's got deep pockets, so he's going to fight more for the upper class," Johnson said, "which leaves people like me kind of stranded in a place that's not so good."

Other voters remain undecided.

On a slow night at Anthony's Pizza & Pasta, the second presidential debate played on the television and delivery driver Kris Ferrin counted his tips.

"Made enough to fill the tank, go back at it tomorrow," he said.

Ferrin, who is 36 and an unaffiliated voter, cursed Obama when he mentioned the theater shooting in Aurora, and he shook his head at Romney's social views.

"You've got somebody that wants to push us back to the '50s and another who's going to make us socialist," Ferrin said. "I don't want either one."

Outside of town, at the Whispering Pines Church, Young said he does not know how he will vote. The 46-year-old unaffiliated voter said he and his wife will talk about it soon.

"We're going to sit down with a sheet of paper and do the pro/con thing, and then we're going to pray about it," Young said. "I've never been so torn."

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