People outside the US are confused, with good reason, about how US elections work and one of the mysteries is how the results are ‘called’. In most countries, after the votes are tallied, an official certifying body declares the winner. While there are often exit polls that might predict the outcome before the official announcement, in practice the official call usually comes so quickly after the count that it does not matter.

But in the US, there is another layer between the vote count and the official certification because what voters are voting for are members of something called the Electoral College and it is these people who then vote for the president about a month later, although they are expected to vote according to how their state voted on election day. Since the result only becomes official on January 6, 2021 when Congress formally certifies the electoral college votes that were cast on December 14, we see that there is a two month gap between election day and the final certification.

So in the US we have the phenomenon of the media ‘calling’ the results for each state when they feel that they are sure what the final outcome will be. They base this on the actual vote counts as they come in plus statistical models based on how votes were cast in previous elections. As I have written before, this method works reasonably well when voting patterns are stable and history becomes a good guide. But this election is anything but, partly due to the extreme volatility of Trump, partly due to the effect of the pandemic, and partly due to the large number of mail-in ballots.

Analysts have urged the media companies to exercise caution when projecting results and warned them especially not to rely on the number of precincts reporting since that tends to be skewed towards the votes cast on election day. One of the most respected outfits in projecting results is the Associated Press and the AP has explained what they will be doing this year.

Shortly before the polls close, over 4,000 stringers report to county election centers. When the first polls close, they’ll be ready to start phoning in the raw vote as it is reported by the counties. They’ll place their calls to AP election centers around the country, which, due to the pandemic, will be virtual in 2020.
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As votes are entered into the AP system, they must pass through computer programs that set off alerts in cases of discrepancies or apparent inconsistencies with previous voting history or other data. If a clerk enters numbers that show a significant disparity from expected patterns, for example, a popup box appears on his or her screen that summons a supervisor to intervene. 
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In all races tabulated by AP, we provide details on precincts reporting. This figure is the percentage of precincts in a race from which AP has received and is reporting results. In many states, this figure is a reasonably accurate estimate of the amount of vote counted, particularly in those states that do not separately report results for ballots cast in advance from those cast on Election Day.

However, the percentage of precincts reporting can be deceiving. In some jurisdictions, election officials may report all of the advance vote as being from a single precinct. A precinct may also be counted as reporting, but that does not mean it has released all of its results. This is why it’s possible for more votes to be added to the count in a race even when 100% of precincts are reporting. This issue is often evident in a race where mail ballots may be accepted and counted well after Election Day. This is not a new phenomenon, but it will be a factor in more states in 2020 due to the expansion of advance voting brought on by the coronavirus pandemic.

In states that primarily conduct their elections by mail, or use vote centers in which voters from any precinct in a jurisdiction can cast their ballot at one of many locations, AP may choose to use an estimate of precincts reporting. This “proportional precincts” figure is calculated by dividing the total vote reported in a jurisdiction by the expected turnout in that jurisdiction.

If AP is using proportional precincts in a jurisdiction, it applies to all occurrences of precincts for all races reporting in that jurisdiction. When using proportional precincts, AP’s precincts reporting figure may not match those posted online by state and county election officials.

All clear? I didn’t think so. All we can hope for is that the media outlets exercise caution and not rush to be the first to report the results because any error will cause great confusion. It is always better to be right than to be first.