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It was called the “red mirage” or the “blue shift.”

This is the latest phenomenon in which an apparent Republican lead early after election night is wiped out by the counting of mail-in ballots later that evening or in the days following Election Day.

Former President Donald Trump pointed to the red mirage to support his baseless claims of voter fraud, when in reality it was due to the increase in 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 in 2020, November 3rd, The end result was anything but clear. The contest between Trump and Joe Biden was too early to include the key states of Arizona, North Carolina, Nevada, Wisconsin, Michigan, Maine, Georgia and Pennsylvania.

Dramatic hours were spent in the following days watching the counting of votes in these states. The vote count did not reflect a Biden lead in Georgia until the early morning of November 6, when small amounts of votes were counted, impacting 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 take this year?: There are indications that things could move faster in some key states.

In Georgia, a new election law means more people will vote sooner in person rather than by mail, which could speed up the counting of 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 will predict a winner when it's clear who will win, the races aren't officially confirmed until later. Certification deadlines vary by state, but all have until Dec. 11 to complete recounts and resolve disputes if necessary Presidential results.

Read more about the “red mirage” or the “blue change” Here.