Everyone remembers where they were when the 2020 election results started trickling in. If you were a political junkie, you probably had a tab open to FiveThirtyEight. Nate Silver was the guy everyone looked to for some kind of statistical sanity in a year that felt anything but sane. But then the night actually happened. It wasn't the "blue wave" the polls seemed to whisper about. It was a grind. A long, stressful, several-day slog that left a lot of people asking: Was the Nate Silver 2020 prediction actually right, or did the models fail us again?
Honestly, the answer is kind of both.
The headlines often paint it as a binary—either the "math guy" nailed it or he was totally off. But if you actually look at the final FiveThirtyEight forecast, the nuance is where the real story lives. Silver’s model gave Joe Biden an 89% chance of winning. In the world of probability, that’s a heavy favorite, but it’s not a certainty. It's the same odds as a kicker making a 30-yard field goal. They usually make it. Usually. But when they miss, it isn't because the physics of football broke; it's because that 11% chance of a miss finally showed up.
The 2020 Prediction: By the Numbers
On the eve of the election, the forecast was pretty stark. Biden was projected to win the popular vote by about 8 points. He ended up winning it by about 4.5 points. That’s a "miss" in the sense of precision, but it’s well within what statisticians call a "normal" polling error.
Here is what the final Nate Silver 2020 prediction actually looked like on November 3:
- Biden win probability: 89 in 100
- Trump win probability: 10 in 100
- Tied chance: Less than 1 in 100
- Projected Electoral Votes: Biden 348, Trump 190
In reality, the map looked different. Biden ended up with 306 electoral votes, while Trump took 232. Florida was the big heartbreak for the model-watchers, where Silver's average had Biden up by 2.5 points, only for Trump to win the state by 3.3. That's a nearly 6-point swing.
Why does this matter? Because the model didn't just give a single number. It ran 40,000 simulations. In many of those simulations, Trump won. In many others, Biden won but it was "close and weird," which is basically what we got.
Why the Polls Felt "Wronger" Than They Were
People tend to forget that 2020 was an outlier year for... well, everything. We had a global pandemic. We had massive shifts in how people voted (early and by mail). Pollsters were terrified of repeating the "hidden Trump voter" mistakes of 2016.
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Silver often defended his model by saying that he built it specifically to account for the possibility that the polls could be wrong in the same direction across several states. This is called "correlated error." If the polls are off in Pennsylvania, they are probably also off in Michigan and Wisconsin. Because his model baked that in, he gave Trump a 1 in 10 chance, whereas other models—like the one from The Economist—gave Biden a 90% or even 95% chance.
Silver was the "pessimist" among the quants. He kept telling people that a Trump victory was "one normal polling error away."
The Florida Factor and the Rust Belt Scares
If you look at the state-level data, the Nate Silver 2020 prediction was a bit of a mixed bag. The model was very confident about the "Blue Wall" returning to the Democrats. And it did! Pennsylvania, Michigan, and Wisconsin all flipped back to Biden.
But the margins were thin.
In Wisconsin, the final FiveThirtyEight polling average had Biden up by 8.4 points. He won it by 0.6. That is a massive discrepancy. If you’re Nate Silver, you point to the fact that the model still had Biden winning. If you’re a critic, you point to the fact that an 8-point lead shouldn't evaporate into a 0.6-point nail-biter.
The issue wasn't the model's math; it was the raw ingredients. The polls themselves were skewed. Whether it was "non-response bias" (Republicans being less likely to talk to pollsters) or "social desirability bias," the data coming in was fundamentally tilted. Silver's model can only be as good as the numbers it’s crunching.
The "Fat Tail" Defense
One thing Nate Silver is famous for is his "fat tails." This is just a fancy way of saying he leaves more room for crazy, unexpected outcomes than other analysts.
In 2020, he was criticized for being too cautious. People wanted him to say Biden had it in the bag. He wouldn't do it. He insisted that if the polls were off by just 3 or 4 points—which is historically very common—the race would be a toss-up. He was right about the uncertainty, even if the "point estimate" (the 8-point lead) was wrong.
What This Means for Future Elections
So, did the Nate Silver 2020 prediction "fail"?
If you view a forecast as a weather report, he told you there was an 89% chance of rain. It rained. But it wasn't the hurricane some expected, and the sun came out a lot sooner in some places (like Florida and Ohio) than he thought it would.
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The big takeaway from 2020 is that we should stop looking at these models as "prophecies." They are snapshots of probability based on imperfect data.
Actionable Insights for the Next Cycle
If you’re following election models in the future, keep these three things in mind to avoid the 2020 stress-loop:
- Ignore the "Headline" Percentage: Don't focus on the "89%." Focus on the 11%. If you can't live with the 11% outcome happening, then the race is too close for your comfort.
- Watch the "Tipping Point" State: In 2020, Silver correctly identified Pennsylvania as the most likely state to decide the election. He was right. Even if the margin was off, the geography of the win was largely correct.
- Check the "Fundamentals": Silver’s model uses things like the economy and incumbency, not just polls. In 2020, the fundamentals and the polls were arguing with each other. When that happens, the result is usually somewhere in the middle.
The reality is that Nate Silver didn't "miss" 2020 in the way he was accused of missing 2016. He gave Biden a win, and Biden won. But the sheer "closeness" of the victory compared to the "decisiveness" of the polls proved that data journalism still has a long way to go in understanding the American voter.
Next time you see a Nate Silver prediction, don't look for a winner. Look for the range of possibilities. That’s where the truth usually hides.
To get the most out of election data, you should compare FiveThirtyEight’s aggregates with other sources like RealClearPolitics (which uses simple averages) and the "Silver Bulletin" (Nate's newer independent project). Seeing where they disagree is usually more informative than seeing where they agree.