After the polls close on Election Night, ABC News and the other major networks will start projecting winners and “calling” races, in some cases well before the official vote counts are finalized.
They’ll do it by relying on data from a New Jersey-based company called Edison Research.
Edison provides exit polls, survey data, and vote counts for ABC, NBC, CBS, and CNN. The company has provided data for this group of networks, known as the National Election Pool, since 2004.
“We know what we're doing is really, really important,” said the company’s president Larry Rosin.
In certain races, networks will project a winner shortly after the polls close, sometimes before state election officials report any official vote totals. Such a projection is nicknamed an “insta-call” in the news business.
Networks only make insta-calls in races where Edison’s exit polls and telephone surveys in the days leading up to the election show a decisive winner, Rosin said.
ABC News only issues a projection when statistical models overseen by a team of mathematicians and elections experts show a winner with 99.5 percent confidence.
Each network has its own team of experts that crunch Edison’s numbers. Fox News makes projections based on data provided by the Associated Press.
When a race is close, the network decision teams turn to more complicated math.
“It’s a matter of looking at that historical vote all the way down to the precinct or county level and comparing how the vote is coming in, in that state up to that point,” said Rosin.
On Election Night, Edison has thousands of employees fanned out in virtually every county across the nation, monitoring the vote count as it comes in and manually reporting the totals when necessary. There are other employees whose job is to check the numbers for accuracy.
Edison’s data helps networks understand how preliminary vote totals compare to the way regions voted in the past, which is an important metric in an election forecast.
“If every precinct was just a little bit more Republican than it had been four years ago, you have a good sense that all the other precincts that are similar will likely be a little more Republican, and the Republican will do a little better than four years ago,” Rosin said as an example.
Using those kinds of trends, the networks then forecast how many ballots are still left to be counted, and what kind of ballots those are -- either in-person early votes, in-person votes on Election Day, or mail-in votes.
At that point it comes down to a formula, comparing the known reported votes to the outstanding votes a candidate is likely to gain.
“It’s a very high-pressure project, but I’m proud to say that no network has made an incorrect call since the 2004 cycle,” which was Edison’s first year providing election data to the networks, Rosin said.
The company started doing this after the debacle in 2000 when networks incorrectly called the race in Florida between George W. Bush and Al Gore. Rosin said a lot of things have changed since then.
“The pressure to make calls correctly really superseded the pressure to call quickly,” he said.
This year could be a challenging one to forecast, Rosin said, with so many more mail-in ballots because of the pandemic. Mail-in ballots take longer to process because election workers have to compare the signature on the mail-in ballot against the signature a voter has on file.
For that reason, Rosin said it may take a while for the networks to call races in certain key battleground states that start their counting process late, like Pennsylvania and Michigan.
This story was first reported by Derek Staahl at KGTV in San Diego, California.