George Gallup had something to prove: Straw polls were useless.

The typical method for a straw poll in the 1930s went like this: A newspaper or magazine printed a sample ballot in its pages, and readers would fill it out and send it in. Based on all of the responses, the newspaper would make a prediction.

Gallup, who had pursued a PhD in psychology and worked in ad research, thought straw polls were nonsense. Really, you were just surveying the type of people who read the newspaper, cut something out and mailed it. Not exactly representative of the electorate.

Rather than measure the opinion of a large number of the same type of person, Gallup developed a system of “quota sampling” — surveying a small cross-section of Americans who mirror the demographics of the entire population — to get a supposedly more accurate measure. In the United States, he calculated that could be done with 3,000 people from different regions and of different ages, races, educational backgrounds, etc.

That’s how Gallup ushered in the modern era of polling — a method that failed to predict Donald Trump’s victory over Hillary Clinton in 2016 and got the strength of the president’s support against Democratic challenger Joe Biden wrong again this week.

While the nation waits for an outcome in the agonizingly close 2020 election, it’s worth examining how we came to rely on polls.

As historian Jill Lepore explained in the New Yorker in 2015, the word “poll” used to mean “head,” as in, the thing being counted when voting “involved assembling (all in favor of Smith stand here, all in favor of Jones over there).” The term “straw poll” evolved from an old expression about throwing hay into the air to see which way the wind was blowing, according to William Safire.

In the mid-1930s, Gallup got an important ally to help prove his theory. In her memoir “Personal History,” Washington Post publisher Katharine Graham wrote about her father, then-publisher Eugene Meyer, taking interest in his new polling method. At the time, Gallup’s “polls weren’t taken very seriously,” she wrote, but “ever the logical thinker, and having always put a premium on the importance of research, my father signed the first contract with Gallup and ran his polls on the front page.”