As Election Day wraps up, the nation awaits the final results of the presidential race between President Donald Trump and former Vice President Joe Biden.

However, experts are warning that without mail-in ballots fully accounted for, the current numbers may be an overestimation of Republican votes in what they're calling a "red mirage."

To take into account mail-in ballots, final voting tallies in key battleground states including Wisconsin, Michigan, and Pennsylvania will not be clear until Wednesday at the earliest, according to NBC. Meanwhile, Bloomberg claims the process might even take up to several days.

What is a 'Red Mirage'?

Red Mirage
US Presidential Election results as of 12:42 a.m on Wednesday. DDHQ

The current election results in the hotly-contested states reflect only Election Day votes, which are leaning towards Trump, creating a red mirage.This is where the results are expected to look rosy for Trump early in the night but could end up swinging in favor of Biden once all the mail-in votes have also been counted.

This is because while Democrats have embraced the option to vote early, either via mail-in ballots or absentee voting, those votes are typically expected to be cast in favor of Biden. Republicans, on the other hand, have indicated they are much more keen to vote in-person on election day, which means Election Day votes will go to Trump.

Therefore, once the mail-in votes are taken into account in these states, the balance could tilt in favor of the Democrats, in a phenomenon that is known as the "blue shift."

Millions of Votes Yet to Be Counted

Biden vs Trump
As per latest polls, Democratic nominee Joe Biden has a slender lead over Republican nominee Donald Trump ahead of the November 3 election Wikimedia Commons

Experts have noted that due to unaccounted ballots, the numbers as they currently stand are nowhere near final. As of Wednesday morning, President Trump was leading in Michigan, Wisconsin and Pennsylvania, but a significant number of votes are yet to be counted.

For instance, Pennsylvania reported at 11:30 p.m. that only 4.9 million votes out of an expected 7 million were counted. Trump currently holds a 56.5% lead over Biden's 42.1%.

Experts have since taken to Twitter to warn others that what they're seeing right now is a red mirage that could see a blue shift in the coming days.