WASHINGTON (AP) —

Maricopa County, Arizona, has become the nation’s quintessential swing county — a place that could determine whether Democrat Kamala Harris or Republican Donald Trump is the next president and which party controls the U.S. Senate.

The county is so divided politically that it can sometimes take more than a week to find out who won. This year, election officials are warning that counting all the ballots in Maricopa could take up to 13 days.

The drawn-out count has made Maricopa County — home to Phoenix and dozens of other communities — a center for election conspiracy theories.

But the reason it takes so long is simple. Here are a few things to know about this massive battlefield:

It’s a sprawling and rapidly growing county

Maricopa County covers more than 9,000 square miles, the size of more than four U.S. states. With its 4.5 million residents, the county is home to 60% of Arizona’s voters. It has more residents than nearly half of the states in the country.

It was not always this way. In 1969, the county still had fewer than a million residents. It has become a magnet for conservatives like John Kavanagh, a retired New York Port Authority police officer who in 1993 moved with his family to Maricopa County.

Kavanagh was like many others who moved to Arizona in the 1990s – middle-class people fleeing colder places and what they saw as economic and political dysfunction around them – for a sunny city , affordable and what they perceived as a cleaner city.

In 1993, the county’s population was 2.3 million, and Republicans dominated the state legislature and Maricopa County politics.

Today, the county is almost double the size and its politics have changed. Arizona now has a Democratic governor, elected in 2022. Its two U.S. senators were elected Democrats.

How Maricopa went from GOP stronghold to swing county

One of the reasons for the change in Maricopa County’s political leanings was increased migration to Arizona from Mexico.

In the 1990s, President Bill Clinton’s administration strengthened California’s border, pushing illegal immigration into Arizona, which already had a large Hispanic population. Immigration quickly became a political flashpoint, leading many in the state’s already large Latino population to believe Republicans were demonizing them.

The most significant change occurred in 2010, when the Republican-controlled Arizona legislature passed a law, SB1070, that allowed local police to arrest people they suspected of found illegally in the country. The law, which opponents dubbed “Show Me Your Papers,” was the nation’s toughest anti-immigration law, and it inspired the state’s Latinos to organize against Republicans.

It “galvanized the Latino community like never before,” said Joe Garcia, leader of the Latino activist group Chicanos Por La Causa.

Yet the first rumors that Maricopa County might oppose the long-dominant Republican Party didn’t occur until 2016.

Republican voters like Gordon Keig were increasingly concerned about some GOP positions.

Keig couldn’t bring himself to vote for Trump or his 2016 rival, Hillary Clinton. And once Trump came to power and began what Keig saw as his erratic, feud-driven approach to governing — including fights with popular Arizona Republican Sen. John McCain, whose own daughters Keig knew the grandchildren – Keig couldn’t take it anymore. He changed his registration to the Democratic Party, saying he felt like Republican values ​​”weren’t there for me anymore.”

In 2020, Keig voted for Democrat Joe Biden. The shift in voters like him is visible by comparing Maricopa’s votes in the 2012 presidential election with those in 2020. A crescent of wealthier neighborhoods surrounds central Phoenix from the north to the southeast, where a new chip factory Intel attracted high-tech workers, shifted from Republican to Democratic. Local officials nicknamed the area “the turnaround zone.”

The inverted area largely follows places where Maricopa’s more educated residents have clustered. Once less educated than the national average, the county now has a slightly higher share of adults with a four-year college degree than the national average — a key indicator of Democratic voting in the Trump era.

The county has become a hotbed of Trump’s lies and election plots.

Trump falsely claimed to have won Arizona after his loss to Biden in 2020, and he and his allies attacked anyone who claimed otherwise.

Supporters gathered outside the county election office, some armed and many waving Trump and American flags, for a “Stop the Steal” rally. Trump’s lawyer at the time, Rudy Giuliani, held hearings at a Phoenix hotel.

The Republican-controlled state Senate has launched an error-riddled review of Maricopa’s handling of the 2020 election. The county has become something of a tourist attraction for election deniers from other states to watch the show.

County Recorder Stephen Richer, a Republican who has defended the accuracy of the county’s election results, has been criticized by Trump himself, and Richer and his family have been threatened.

Richer says the reason some Republicans remain skeptical of how elections are being conducted in the county is not because there is anything particularly complicated or unusual about the way votes are counted . That’s because Maricopa — where Biden beat Trump by a margin of about 11,000 votes — might be the best place to undermine confidence in national elections.

Maricopa is a swing county in a swing state, he noted.

“So if you really wanted to focus your attention on a place that would pay dividends for your theories, then Maricopa County would be the perfect place,” Richer said.

Why a complete count takes time

Conspirators have seized on the way Maricopa reports vote counts all at once after Election Day, then in dribs and drabs for more than a week, when it finally becomes clear who won. There are three main reasons for this: Maricopa’s size, the proximity of races in the county, and Arizona’s election laws, which were written and approved by Republicans.

Maricopa is the second largest voting jurisdiction in the country. Only reliably Democratic Los Angeles County is larger.

Maricopa releases its results much more quickly than Los Angeles, but it takes longer to find out who won because the county — and Arizona as a whole — is evenly split. This creates a false impression of disorder in the vote count.

Arizona’s mail-in voting law also delays the count. It allows voters to return their absentee ballots before the polls close on Election Day. In 2022, 293,000 voters – or one-fifth of the vote total in Maricopa – cast their absentee ballots on Election Day.

Counting mail-in ballots takes longer because, before they can be counted, envelopes must be scanned, ballots sorted, and voter signatures inspected to ensure their legitimacy. Some states, like Florida, require all mail-in ballots to be cast before Election Day, so this process is completed when the polls close. Due to Arizona law, Maricopa’s polling location closures are just beginning.

Extending the count even longer is a provision of Arizona law that allows voters to “cure” their ballots up to five days after Election Day. This means that if the election office believes that the signature on the ballot or any other technical detail is wrong, the voter has five additional days to come and correct the problem so that the ballot counts.