Chris Cooper was surprised by what he found.

While researching his 2024 book Anatomy of a Purple State, the political scientist examined decades of presidential races in the United States, combing through polls, studies and newspaper archives.

He found that, in the last 12 presidential elections, North Carolina functioned as a “swing state” in all but one contest — a 1984 blowout by incumbent Ronald Reagan.

It was an eye-opening revelation for Cooper, given that North Carolina has only recently been embraced as a coveted prize in the country’s presidential races.

This year, North Carolina is considered one of seven pivotal battlegrounds where the outcome of the November 5 presidential race is unclear.

It could lean towards the Republican candidate, Donald Trump, or it could tilt towards his Democratic rival, Kamala Harris. In a tight race, a win in the southern state could help catapult either candidate to victory.

But for Cooper, North Carolina’s newfound notoriety as a kingmaker is the culmination of decades of shifting trends.

“We have a longer experience as a battleground state than I understood,” Cooper told Al Jazeera.

What defines a swing state is often a narrowing in the polls.

Generally, when the margin of victory falls below three percentage points in a given state, pollsters and political campaigns take note: The area is deemed competitive. A swing state is born.

But the competitiveness of North Carolina has often been overlooked, in favour of other swing states like Pennsylvania and Michigan.

Part of the reason is political. Since the 1960s, the southern region of the US — North Carolina included — has voted reliably Republican in presidential races. The state has only backed a Democrat twice over the last 50 years: in 1976 and 2008.

It has also grown famous as the birthplace of prominent right-wing figures like Jesse Helms, a 30-year senator who was arguably one of the most conservative US politicians of the 20th century.

North Carolina, however, has a more complex history than broad regional trends suggest.

Many scholars argue it was even a bastion for Southern progressivism in the early 20th century, making strides in public welfare, education and other reforms.

And in recent decades, its left wing has been nearly as strong as its right. In 2008, Democratic presidential candidate Barack Obama beat Republican John McCain in the state by only about 14,000 votes.

Its races have been squeakers ever since. In 2020’s presidential race, for instance, Trump had his narrowest victory, out of all 50 states in North Carolina. In the upcoming November 5 vote, polls once again show Trump with a tiny lead over his Democratic rival.

Political analysts like Democratic strategist Morgan Jackson see in North Carolina a state with two distinct political personas.

“North Carolina is one half Virginia, one half Alabama,” Jackson said, juxtaposing two southern states: one more moderate, the other deep red. “It’s a state you win on the margins.”

For his part, Cooper describes North Carolina as “right on the razor’s edge between red and blue”. But it’s a third category — voters who identify neither as red nor blue — that may ultimately decide who wins.

About 20 years ago, in the early 2000s, Paul Shumaker’s party began experiencing a troubling trend.

Shumaker, a Republican operative with a classic Carolinian drawl, laid it out for Al Jazeera in stark terms: Republican registration started declining, while the number of “unaffiliated” voters gradually rose.

“Now there are no liberal Republicans left, and there are fewer moderate Republicans, too,” Shumaker said.

He shared data showing how both major parties, Republicans and Democrats, have, in total, invested more than $147m in the state over the last 10 years — but even that couldn’t stop an “explosion” of unaffiliated voters, who are now the clear majority.

Of the 8.5 million voters in North Carolina this year, approximately 38 percent are registered as “unaffiliated”. That dwarfs the 32 percent who identify as Democrat and the 30 percent who say they’re Republican.

This explosion of “unaffiliated” voters dovetails with larger demographic trends showing Americans bucking traditional party labels, adding to the unpredictability of elections.

However, that doesn’t mean “unaffiliated” voters will opt for a third-party candidate. Surveys have shown that the majority of independent voters do, in fact, “lean” consistently towards either the Republican side or the Democrats.

Which is to say, they’re very much up for grabs — and in demand — by the two major parties.

“Neither party can win without building a coalition for unaffiliated voters,” Shumaker said.

Republicans, he explained, need to appeal to unaffiliated voters in the suburbs and cities — two areas Democrats are expected to win.

Democrats, meanwhile, are hoping to use “unaffiliated” voters to compensate for losses in their base. More than 2.4 million people in North Carolina registered as Democrat as of October 26 — down from more than 2.6 million at around the same point in the 2020 election cycle.

Party strategists like Jackson hope to make up the loss by appealing to voters in left-wing strongholds — typically urban centres — while holding ground in rural areas.

After all, North Carolina has the largest rural population in the US after Texas.

“People often say you have to lose by less in the rural areas, but that’s not true: You just have to stop the bleeding,” Jackson said. “If Kamala Harris holds (outgoing President) Joe Biden’s margins, she could have a shot.”

Mac McCorkle, a Democratic political consultant with a cheery, amiable aura, refers to unaffiliated voters as “precious” to his party. He believes only a small number of voters will decide whether North Carolina backs Harris or Trump.

“It’s not like 20 percent of the electorate can go either way,” he said. “We’re talking about a race that’ll be decided by one, two, three percent.”

The way McCorkle sees it, many Republicans, as well as a number of unaffiliated voters, “hold their noses” and vote for the far-right Trump, despite misgivings about him and his party.

But in such a tight presidential race, McCorkle says a small number of “anti-MAGA people” — named for their opposition to Trump’s nativist “Make America Great Again” movement — could make all the difference in the swing state.

Several strategists interviewed for this story say tolerance for MAGA politicians may be thinner than ever, given the recent accusations levied at gubernatorial candidate Mark Robinson, a Trump-endorsed Republican.

A CNN report indicates Robinson referred to himself as a “Black Nazi” on a pornography message board, alienating some of his base. He has denied the allegations.

“The difference this election is Mark Robinson,” Jackson said. “He’s creating a permission structure for folks to skip Trump.”

McCorkle likewise believes Robinson could be a deciding factor among North Carolina’s moderate and unaffiliated voters, thereby swinging the state in one direction or another.

“Mark Robinson underlines all the things they’re unsure about,” he said.

Even other Republican politicians have noted Robinson’s tarnished reputation as an added wild card in the already volatile swing state.

Republican Scott Lassiter is running for North Carolina’s state senate, and he told Al Jazeera that Democrats are using “guilt by association” to damage the chances of all Republicans in the aftermath of the scandal.

As he assembled political yard signs in his garage, he explained that he had seen multiple Democratic mailers attempting to tie him to Robinson, though he recently called on Robinson to exit the race.

Still, Lassiter argued that the Robinson scandal may have limited effect on whether North Carolina swings to the left or right.

He anticipates residents will vote based on the economy — and that will lead to “folks holding their nose and voting for Trump”.

“They’re doing mental gymnastics to separate Trump the person from Trump’s policies,” Lassiter said.

Whatever the outcome, the state’s tight margins are widely perceived to be a microcosm of a divided nation.

“North Carolina is incredibly polarised, and it’s difficult to see a North Carolina that is less polarised without a country that is less polarised,” said Jackson, the Democratic strategist. “So, this year, all this (in North Carolina) is going to come down to 50,000 to 100,000 votes.”

The state is also seen as a symbol of a changing South. The region still struggles with the legacy of slavery and racial segregation, and its status as a Republican stronghold was established in the 1960s, in part as a backlash to the civil rights movement.

But in recent decades, the South has become more racially diverse. Some scholars have even observed a reversal of the “Great Migration”, when Black people left the region en masse, with many now moving back.

In North Carolina specifically, the state government also noted that the greatest increases in net migration came from left-leaning states like California and New York.

Those population changes have added an extra dimension of ambiguity and surprise to North Carolina’s status as a swing state.

And with 16 Electoral College votes to offer the winning presidential candidate on election night, North Carolina could decide the fate of the race. Shumaker, the Republican strategist, put an even finer point on it.

“What happens in North Carolina,” he said, “basically determines what happens in the nation.”