Politics

US Election Polling Error History: A Complete Timeline

US public polling has underestimated Republican presidential performance relative to Democratic performance in three straight elections — 2016, 2020 and 2024 —…

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THE LITERARY DIGEST DISASTER

2.4 Million Responses — and Still the Wrong Winner

Literary Digest mailed roughly 10 million ballots and got back about 2.4 million responses, predicting a Landon win. Franklin Roosevelt won in a landslide — the mailing…

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DEWEY DEFEATS TRUMAN

America's Most Famous Wrong Headline

Major pollsters showed Dewey comfortably ahead and some stopped fielding weeks before Election Day. Truman won. Quota sampling that gave interviewers discretion over who…

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LATE MOVEMENT, NOT BAD POLL…

Reagan's Landslide Outran the Final Polls

Many late polls showed a competitive Carter-Reagan race; Reagan won by nearly 10 points. Evidence points to genuine late voter movement in the campaign's final days rath…

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NATIONAL VOTE VS ELECTORAL…

Gore Wins the Popular Vote, Bush Wins the Presidency

Al Gore narrowly won the national popular vote; George W. Bush won the Electoral College after Florida's disputed recount. National polling was not badly wrong — the epi…

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STATE POLLS MISS, NATIONAL…

Trump Defeats Clinton in an Electoral College Surprise

National polls implied Clinton +3; the actual result was close to Clinton +2 — a modest miss. The real failure was in state polls in Wisconsin, Michigan and Pennsylvania…

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THE LARGEST MODERN MISS

Biden Wins, But the Margin Was Overstated

Polls correctly called Biden's win but overstated his margin: a 4.5-point national absolute error and 3.9-point signed error toward Biden, more than double 2016's nation…

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NARRATIVE VS DATA

The "Red Wave" That Wasn't — and Polling That Held Up

Pre-election commentary anticipated a large Republican wave; the actual result was mixed. Post-election reviews found the underlying polling performed well by historical…

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ACCURACY IMPROVES, PATTERN…

Trump Defeats Harris as Polling Accuracy Rebounds

AAPOR's review of 611 late-campaign polls found a 3.3-point average absolute margin error, down from 5.2 in 2016 and 5.3 in 2020. State presidential polling was the most…

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THE NEXT ADJUSTMENT

Pollsters Expand Political Weighting After Three Straight Cycles

Pew Research Center reports more pollsters adopting weighting on political variables — party affiliation or recalled past vote — after repeated underestimation of Trump…

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