Election Day is Nov. 3, but even if there's a projected winner, Americans won't know the official result that day. CNN analyst and Propublica reporter Jessica Huseman says that's nothing new.

"We've actually never known the results of Election Night on Election Day, and this year won't be any different," Huseman says.

While projected winners are announced, it has to do with how states count votes.

"The first state to certify its election result is Delaware, and that doesn't happen until two days after the election," Huseman explains.

Then there's the 21 states and D.C that accept ballots post-marked by Election Day, even if they arrive after Nov. 3.

States actually have until Dec. 8, the Safe Harbor deadline.

It's a federal law that's been around since the late 1800s and says states must resolve any election disputes and finalize tallies six days before members of the Electoral College gather to cast their ballots, which means early results could look very different from the final outcome.

And as former Vice President Al Gore explains, the swing will be even wider this year.

"There may be what's called a 'red mirage' that people who vote on the day of the election may be more in Trump's favor and then a blue shift as the mail-in ballots are counted, again, more of them this time than ever before," Gore says.

This could be especially true considering some key battleground states. Iowa, North Carolina, Ohio, Pennsylvania, and Texas are among the states that accept post-marked ballots that arrive after Election Day.

"We have to be patient and let the votes be counted," Gore emphasizes.