The changing face of Arizona is turning a Republican stronghold into a swing state

Once one of the more reliably Republican states in America, Arizona has emerged as a surprise swing state in the 2016 race for the White House.

Demographics in the state are changing dramatically. The growing number of Hispanics here tend to tilt politically toward the Democratic Party, which is upending the traditional balance of power.

• Eric Grenier's Poll Tracker: See what the numbers are saying
• More stories and analysis on the U.S. presidential election

Immigration is arguably the central issue here, and it has turned Arizona into a battleground state in some cases, quite literally.

Many Arizonans applaud Donald Trump's call for a wall along the U.S. border with Mexico as a way to combat illegal immigration and rampant drug smuggling.Supporters of the Republican candidate highlight the many long stretches of Arizona's border that are lined with four strands of easily surmountable barbed wire fencing.

"What we need is a wall through here," said rancher and Trump supporter Jim Chilton. "We need to stop the drugs coming in. For me, it's a big issue."

But Trump's fiery language about Mexicans has frightened many others. Among those backing Hillary Clinton is Linda Mazon Gutierrez, a Mexican-American born in Phoenix.

"I took it very personally when [Trump] came out and said that Mexicans were rapists, that they were criminals," she said, worried that Trump's rhetoric and policy plans will bring trouble.

"You incite hatred, you're going to get hatred," she said. "I am the mother of four children. I do worry about my children. I do worry about them being profiled. I worry about them being target practice."

'Honestly, it makes me sad'

For more evidence of a deeply divided Arizona, you just need to go out to campaign rallies for Trump and Clinton, which are becoming increasingly violent.

Cellphone video from these gatherings, found easily on YouTube, show people throwing punches and kicking, spitting and slapping fellow Arizonans who happen to back the opposing candidate.

"Honestly, it makes me sad," one pro-Clinton demonstrator said last week outside a Phoenix rally to protest an appearance by Trump's son, Donald, Jr. "I don't have words for it."

As she spoke, a pro-Trump demonstrator a few metres away shouted, "You hate us it's not the other way around. You're the fascists."

Along a walkway outside the rally, the Clinton crowd chanted "Si se puede" "Yes we can" in Spanish while Trump backers yelled back, "Lock her up!"

"I've never seen the country so polarized," said Trump supporter Bill Gran inside the rally.

The cost of criticizing Trump

Broad distaste for Trump's rhetoric has enraged many in Arizona, but standing up to the Republican candidate has come with a price.

Just ask the editorial board of the Arizona Republic newspaper.

As a sign of how the political currents have changed, in September, the paper decided to endorse Hillary Clinton for president. It was the first time in the paper's 126-year history it had failed to back a Republican.

It's backing Clinton because it deems Trump unfit for office.

The repercussions were immediate.

"The first death threat came about nine in the morning," said Republic publisher Mi-Ai Parrish, referring to an anonymous phone call made to the newsroom after the editorial was published.

"Because of your endorsement," the caller told the person who answered the phone, "your reporters are going to be blown up."

Parrish said more death threats followed.

"It's a dark time now, you know," she said. "I think there's so much anger and vitriol and unhappiness. It won't go away after the election. It won't just magically disappear."

Concerns about violence

Like others across the U.S., some people in Arizona worry Trump backers will turn to violence if their candidate loses on Nov. 8.

Phoenix County Sheriff Joe Arpaio doesn't believe it. Arpaio endorses Trump, but downplays any talk of violence in the aftermath of a potential election loss.

"Any rumours that there's going to be fighting, it's not going to happen," he said.

Arpaio is a deeply controversial figure in Arizona, infamous for targeting illegal immigrants. He is seeking a seventh term in office, but faces criminal charges related to racially profiling Latinos.

The fact that Arpaio is expected to lose his re-election bid speaks to the changing demographic in the state. But Trump's campaign has clearly galvanized Arizonans who are concerned about existing immigration policies.

So what happens to all the anger among Trump supporters if they don't get the desired result?

"I don't think there's going to be a revolution," Arpaio said. "But people like myself are not going to forget Donald Trump."