Polls of the 2020 presidential election were at their collective worst in 40 years.
No misfire that year was more striking than CNN’s. Its final poll before the election estimated that Joe Biden held a landslide-size lead of 12 percentage points over then-President Donald Trump.
That reading was down from early October 2020, when CNN reported Biden’s advantage stood at 16 points. No polling organization in 2020 reported a greater margin in the presidential race, according to the RealClearPolitics compilation of polls that year.
Biden won the popular vote by 4.5 points, which meant a sizable polling error for CNN and its polling partner, SSRS, a research company in suburban Philadelphia.
As I wrote in “Lost in a Gallup,” my book about polling failure in U.S. presidential elections, surveys conducted for CNN and other major corporate media outlets “possess unmatched if obvious narrative-shaping effects.” Results of their surveys are prominently shared with large audiences, thus helping media-sponsored polls to set the storyline for the election campaign.
“When these pollsters speak, the public listens,” veteran polling analyst David Moore has said. The robust lead CNN reported for Biden in 2020 “clearly was part of the ongoing narrative,” Moore added.
As pollster Mark Penn pointed out after the election,........