Chance, demographics or even people reluctant to voice support for Trump could all be reasons for discrepancy
In the weeks leading up to the 2024 presidential election, Guardian polling averages showed Kamala Harris winning an incredibly close race. Still, Donald Trump won, showing that yet again his volume of support was underestimated.
Though Guardian US averages had Harris winning, the final result was within the margin of errors for high-quality polls conducted this election cycle.
With an estimated 99% of the vote counted, Guardian US national polling averages were off by three percentage points as of 20 November 2024, an analysis of the 2024 presidential election returns has found.
Though this may change as more votes are counted, preliminary results show that polls underestimated the level of support for Trump for the third election in a row. The Guardian US national polling average had Harris at 48% and Trump at 47%, with the final results being Trump 50%, Harris 48%, an error similar to the polling errors in past elections.
Guardian US national averages only took the average of high-quality polls, but swing state polling averages used every poll gathered by 538. There are fewer swing state polls conducted, but are important because national polling is not indicative of who is going to win the election, only the level of support nationally.
Guardian US averages had Trump winning four out of seven key swing states and there was a bigger spread in the accuracy for swing states.
“You don’t have a lot of high-quality polls in swing states in particular,” Andy Crosby, assistant professor of teaching at the University of California Riverside School of Public Policy, said.
