It’s called the “red mirage” or the “blue shift.”

It’s the recent phenomenon in which an apparent Republican lead early after the polls close on election night is erased by the counting of ballots later that evening or in the days after Election Day.

Former President Donald Trump has pointed to the red mirage to support his baseless accusations of election fraud, when in fact it is a result of the rise of mail-in voting and the often peculiar rules about when those ballots can be counted.

What happened in 2020?: As most Americans went to bed on election night 2020, November 3 the end result was far from clear. The battle between Trump and Joe Biden was still too early to involve the key states of Arizona, North Carolina, Nevada, Wisconsin, Michigan, Maine, Georgia and Pennsylvania.

The next few days would include dramatic hours watching the vote counting in these states. The vote count did not reflect a Biden lead in Georgia until early in the morning of November 6, when small batches of votes were counted, affecting the very close election.

CNN was able to predict that Biden would win the election four days after Election Day, on November 7, but counting would continue.

How long will it last this year?: There are indications that things could be moving faster in some key states.

In Georgia, a new election law means more people will vote early in person instead of by mail, which could speed up the process of counting mail-in ballots. North Carolina will no longer accept mail-in ballots if they arrive after Election Day.

It’s important to remember that while news networks like CNN can predict a winner when it’s clear who will win, the races aren’t officially certified until later. Certification deadlines vary by state, but all have until December 11 to complete recounts and resolve disputes if necessary. presidential results.

Read more about the “red mirage” or the “blue shift” here.