The Associated Press will not predict a winner of the presidential election. It will not even name an apparent or likely winner. The AP will make the call only when it is certain — just as it has in every U.S. election since 1848, when Zachary Taylor won the White House.

“If there’s no way for the trailing candidate to catch up, no legal way, no mathematical way, then the race is decided, essentially,” Sally Buzbee, AP’s executive editor, said in an interview. “And if there is any uncertainty, or if there are enough votes out to change the result, then we don’t call the race.”

As the AP tracks the contest between President Donald Trump and Joe Biden, as well as 35 Senate, 11 gubernatorial, 435 congressional and more than 6,000 down-ticket races, its determinations will not be swayed by outside forces.

“Race calls made by other organizations have no bearing on when AP declares a candidate the winner,” the AP said in an article on its website. “Our decision team does not engage in debate with any campaign or candidate.”

That stance may prove crucial in a turbulent election in which more than 90 million Americans cast their ballots before Election Day on Tuesday because of the coronavirus pandemic — an election further complicated by widespread misinformation and Trump’s false claims that the vote has been “rigged.”

The AP bases its determinations on the work of more than 4,000 freelance local reporters who collect vote counts from clerks in every county of the 50 states. Those local reporters phone the results to AP’s vote entry centers, which are virtual this year because of the pandemic. More than 800 vote entry clerks assess the data, checking with the reporters about any anomalies, before entering it into the AP system.

A race caller in each state examines the counts with an analyst at the AP’s politics team in Washington to determine when a winner can be declared. Two editors sign off on every call, Buzbee said. And when the time comes to name the winner of the presidential race, AP’s Washington bureau chief, Julie Pace, has to sign off.

With 250 bureaus in 99 nations, AP provides roughly 730,000 articles, 70,000 videos and 1 million photographs each year to the more than 15,000 outlets and businesses that subscribe to its content.

At election time, it steps into the spotlight: Major news organizations including NPR, PBS, and two large newspaper chains, Gannett and McClatchy, wait for the AP to call races before they report results. Other outlets, including The New York Times, The Wall Street Journal, The Washington Post and Fox News, will use election data from AP to help them make their determinations. Google will use AP’s election reporting for real-time results on its search page, as well as for a panel on YouTube. (ABC, CBS, CNN and NBC make their own calls, but will share information as members of the National Election Pool, a group that uses data from Edison Research.)

“The AP has a track record going back over a century of thorough, careful vote counting and cautious practices when it comes to calling races,” said Arnie Seipel, NPR’s supervising political editor. “They also have a decision desk with vast resources to do this kind of data collection and analysis. So by relying on the AP, we are able to invest more of our resources into original reporting, instead of trying to replicate what they do.”

In the United States — which, unlike many other countries, does not have a national electoral commission — the news media takes the role of race-caller in presidential elections. “If we want to know who the next president will be, we’ve got to do the math ourselves — county by county, nationwide,” David Scott, a deputy managing editor at the AP, said in an article posted on its website.

Buzbee, who has worked at the AP since 1988 and became its top editor in 2017, said the staff was well aware of its election role. “We take it enormously seriously,” she said. “We know the impact we’re going to have when we call the race for president. We know it’s going to zip around the world.”

The AP was the first news organization to declare Donald Trump the victor of the 2016 election. It published a straightforward news alert at 2:29 a.m. EST on the day after Election Day: “WASHINGTON (AP) — Donald Trump elected president of the United States.”

AP did not declare the victor of the 2000 election between George W. Bush and Al Gore, deciding that it was too close to call. That time, the job of naming the winner fell to the Supreme Court.

Because of the pandemic, most of the AP’s staff members have been working remotely since March. On Tuesday, about 50 of “the core folks” will work in the Washington bureau, rather than the usual crew of 200 journalists, Buzbee said. Instead of the usual shared pizzas, there will be boxed dinners.

Any chance of making the call for Trump or Biden on Tuesday night or the early hours of Wednesday? “If one of them is winning by a large margin and we have a handle on how many mail-in ballots remain outstanding, then it could be called on election night,” Buzbee said. “If it’s a close race, it will be later.”

After AP declares the winner, it will publish articles about how it arrived at its call. “We’re trying to do that so we demystify the process and no one thinks this is happening in a black box,” Buzbee said.