National polls certainly picked the right winner. Every poll released in the month before the election found Biden leading — and he easily won the popular vote.

Averaged together — always the best way to look at the data — state polls also predicted the presidential winner in every state but two. In Georgia, the averaged polls gave President Trump a slim one-point lead but voters preferred Biden by an even smaller margin. In Florida, polling suggested a Biden advantage of less than one point, but Trump won by more that 3 percent.

Leaving aside Maine, which obviously suffered from unique problems, Senate surveys accurately pegged the vote for Democrats, but consistently underestimated support for Republicans.

On average, public Senate polls came within a point of the vote for Democratic candidates but missed support for Republicans by almost four times as much and, again, in every case understated GOP support.

Decades ago, pollsters’ inside secret of was that undecideds broke overwhelmingly to the challenger.

One of my first races pitted an unknown against a House incumbent in Connecticut. Six weeks out, we were behind by 48 percent to 25 percent. I cautioned the candidate to ignore the margin, noting that most of those undecideds would come our way. And in the end, we won.

But what was once a law of polling no longer rules.

Human brains and eyes naturally gravitate to margins — because margins quickly summarize the data. But like all summaries, they can obscure, or ignore, important information.

There’s a difference between a contest where a candidate leads 53 percent to 45 percent, with 2 percent undecided, and one where the lead is 46 percent to 38 percent with 16 percent undecided. The eight-point margin is the same, but the contours of the race, and the outcomes, could well be quite different.


Focusing on margins while failing to understand the role of undecideds is not an error in the poll, it’s a mistake in analysis and interpretation. So is relying on any one poll instead of an average.

The lesson of this cycle is not the demise of polling, but the need to include all the data and perhaps most importantly, to devise a way to predict, in advance, how the undecideds will fall.
For decades, I’ve searched in vain for this great white whale. I hope someone finally reels it in.