Colorado's 4th congressional district (CNN) When it comes to the fate of the GOP's health care bill, no district is more important than this swath of eastern Colorado.

Rep. Ken Buck is one of several Republicans who have said they might vote against their party's effort to repeal and replace Obamacare

That has raised tensions in this largely rural district.

"We should pass it as is now and go to the next step," said Mark Strodtman, who fixes and sells cars in the district's largest city, Greeley.

Strodtman said he doesn't think the GOP bill is perfect the way it's written now. But he said he can't stand Obamacare and says it's time to "wipe it off the map."

While Strodtman is a staunch Republican and huge Trump supporter, all five of his adult children are Democrats.

It's far from the only division in this new political hot spot.

Farms, cattle and health care debates

This is a district where farmland dominates the landscape, where working-class people gather at the local diner to talk about life's daily minutiae. One local talks about struggling to buy new tires. Another wants to know how to get kids to behave.

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But mention the topic of health care, and everyone's eyes grow wide. Their voices grow passionate.

"When it comes to health care, the whole system is messed up," said Billy Castillo, a hospice nurse in Greeley.

Castillo said he's glad his congressman is leaning toward voting against the GOP bill.

"This new bill won't solve the situation," he said. "It's just Obamacare light."

Others had more heated words about the health care system.

"Obamacare is a catastrophe because it's horribly expensive," David Barber said. "The government keeps giving and giving and giving, and it's got to stop somewhere."

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Barber and his wife, Linda, have lived in the Greeley area for 24 years. He's a truck driver and Army vet; she's a retired drug- and alcohol-abuse counselor.

Linda Barber gets worked up at the mere mention of "health care" and said the system needs to be overhauled.

"We take care of ourselves, and we're healthy. And I'm paying for unhealthy people to go to the doctor. Why don't you just take care of yourself?" she said.

"We are paying higher taxes and paying for their health care when they should be taking care of themselves like we are."

Both David and Linda Barber said they don't understand all the nuances of the GOP's bill to repeal and replace Obamacare. But they both said they trust their congressman's judgment.

Critical votes

The GOP needs a simple majority -- 216 votes -- for its bill to pass the House. And since the House is GOP-controlled, it can afford to lose as many as 21 Republican votes.