But within the next minute, NBC, CBS, MSNBC and ABC projected the same. The Associated Press made the call at 11:26 a.m., and Fox News called it at 11:40 a.m.

The Washington Post made the call at 11:34 a.m. that Biden won Pennsylvania and the presidency.

Each news outlet makes its own determination on these calls, relying on “decision desks” staffed by political scientists, researchers and analysts who operate independently from newsroom political staffs. The AP and Fox News were the first major news organizations to call Arizona, which meant that for several days their counts had Biden at just six electoral votes shy of the 270 needed to win the presidency. Fox News called Arizona for Biden at 11:20 p.m. Tuesday, and the AP followed suit at 2:50 a.m., Wednesday.

None of the other major news organizations, which rely on data firm Edison to make race calls, have projected a winner in Arizona or Nevada yet because of a lack of clarity around the number and type of ballots that remain to be counted.

Fox’s projection that Biden would be the next president came at the same time as it called that he would win Nevada’s six electoral votes, followed by the AP about 30 minutes later. Most other media organization have not yet called Nevada, which means that Fox and AP are touting a higher total electoral vote tally for Biden of 290 than their competitors.

Fox and the AP use different data than counterparts to make these analyses, having joined together after the 2016 election to hire a University of Chicago-affiliated research operation. AP VoteCast, which conducts surveys online and by phone, is also used by NPR, “PBS NewsHour,” Univision, USA Today and the Wall Street Journal – all of which have called Arizona for Biden. At Fox, the data set is called Fox News Voter Analysis, and its decision desk makes the network’s calls.

The early Fox News call on Arizona drew the ire of the Trump campaign, which sent out an email missive attacking by name Arnon Mishkin, the management consultant who runs the network’s decision desk. When asked about the campaign’s insistence that the outstanding votes left to be tabulated will be sufficient for Trump to overtake Biden’s lead in the state, Mishkin, explained why his team didn’t see a path forward possible, adding “if a frog had wings.”

Other news organizations had been weary of calling Arizona for Biden, where his lead is slimming as more votes are tallied. “In Arizona, it is getting really, really close,” John Lapinski, NBC director of elections, said on MSNBC on Friday morning. “I know other people called that race on election night. Those were kind of crazy calls. This race could go down do to the wire, and we’re just going to have to see and it will depend on if President Trump, you know, does as well as the earlier batches. And if that’s the day, he could win this. I think I’d rather be vice president Biden because he has a slight edge, but ever so slight.”

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