Predicting exactly how Election Day will run can be a dangerous game, as plenty of people learned on Tuesday — but Bernie Sanders got pretty damn close.

An old clip of the Vermont senator and former Democratic presidential candidate on The Tonight Showin October is doing the rounds as we await results of the U.S. election — despite Donald Trump's unfounded and false claims of early victory.

In the Oct. 23 interview, Sanders explained to host Jimmy Fallon why he endorsed Biden for president after running against him for the nomination and discussed the role of Texas in the future of progressive politics. But most importantly, he laid out why this year's election results would take longer than usual — and what Trump's reaction on election night would likely be.

"Although the election is November 3rd and it's been said that we won't know the results until days later, when do you think we'll know the results?" asked Fallon at the time.

"Jimmy, you raise an important point, and I hope the American people understand it, because this is something I worry about," began Sanders.

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"My view is every vote must be counted. For reasons which I don't have the time to get into tonight, you're going to have a situation, I suspect, in states like Pennsylvania, Michigan, Wisconsin, other states, where they are going to be receiving huge amounts of mail-in ballots. And unlike states like Florida or Vermont, they're not able, for bad reasons, to begin processing those ballots until, I don't know, Election Day or maybe when the polls close. That means you're going to have states dealing with perhaps millions of mail-in ballots."

Sanders is right — a record 64 million mail-in ballots were sent before Election Day, which is complicating the vote count this year. Key battleground states Pennsylvania, Wisconsin, Michigan, and Georgia received significant amounts of mail-in ballots — and in Pennsylvania, for one, the Trump campaign and Republicans blocked the processing of votes ahead of Election Day. This has caused a delayed vote count that could run into the week.

"Here is my worry," Sanders said. "What polls show, and what studies have shown is that, for whatever reason, Democrats are more likely to use mail-in ballots, Republicans are more likely to walk into polling booths on Election Day. It is likely that the first votes that will be counted will be those people who came in on Election Day, which will be Republican.

"And here is the fear — and I hope everybody hears it," continued Sanders. "It could well be that at 10 o'clock on election night, Trump is winning in Michigan, he's winning in Pennsylvania, he's winning in Wisconsin, and he gets on the television and he says, 'Thank you, Americans, for re-electing me. It's all over. Have a good day.' But then, the next day, and the day following, all of those mail-in ballots start getting counted, and it turns out that Biden was won those states, at which point Trump says, 'See? I told you the whole thing was fraudulent. I told you those mail-in ballots were crooked. And we're not going to leave office.' That is a worry that I and a lot of people have... people should be aware of that possibility."

It was in the earlier hours of Wednesday, not 10 o'clock on election night. But despite incomplete results, citing (among others) those Midwestern states where he was ahead in the still-incomplete counts, Trump did falsely claim victory over Biden —both in a televised address to supporters at the White House and on Twitter and Facebook, in a clear declaration of intent to manipulate the electoral process.

SEE ALSO:Twitter puts warning label on Trump's false election tweet

"Frankly, we did win this election," Trump said, even though millions of votes, including key results from Pennsylvania, Wisconsin, Michigan, and Georgia, have not been fully counted, and no major news outlet had declared a winner. "We’ll be going to the U.S. Supreme Court," he added. "We want all voting to stop." It wasn't a total surprise that Trump declared this premature, false victory, but Sanders even got the states right.

Tweet may have been deleted

It's undeniable: Bernie called it.

TopicsThe Tonight Show Starring Jimmy FallonBernie SandersDonald TrumpJoe BidenPolitics