Voter preference polls aren’t meant to predict victories. They are snapshots in time that help news outlets and the general public better understand what likely voters are thinking and what issues are important to them at that moment.
But many look to polls conducted shortly before an election to get a better sense of how Election Day might go.
In Iowa, The Des Moines Register has been conducting the Iowa Poll since 1943, when it first had pollsters fan out across the state to interview Iowans on their doorsteps. Since 1987, J. Ann Selzer has led the Iowa Poll, first as a Register staffer and on a contract basis since 1997 with her firm Selzer & Co.
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When an Iowa Poll is released, readers often wonder how close past polls have tracked to the eventual election results. Here’s a look at Iowa Polls ahead of U.S. presidential elections for the last 20 years.
2020: Final Iowa Poll shows Donald Trump with lead over Joe Biden
The final 2020 Des Moines Register/Mediacom Poll was conducted Oct. 26-29, 2020, just days ahead of the Nov. 3, 2020 election. The results showed then-President Donald Trump leading in the state: 48% to Joe Biden’s 41%.
The 7-point lead was a shift from a September 2020 Iowa Poll that showed the race in the state was tied.
It aligned closely with the final results when Trump won Iowa by 8 points (53% to 45%).
More: Could Iowa be shifting back to a presidential swing state? What the new Iowa Poll shows
2016: Final Iowa Poll shows Donald Trump beating Hillary Clinton
After voting for President Barack Obama in back-to-back elections, Iowa saw plenty of campaigning from both Donald Trump and Hillary Clinton in 2016.
The final Des Moines Register/Mediacom Iowa Poll showed Trump with a 7-point lead over Clinton (46% to 39%). The poll was conducted Nov. 1-4, 2016, ahead of the Nov. 8, 2016, election.
It took until 1:30 a.m. the next day for the Associated Press to call the race for Trump. Trump finished with a 9.4-point lead over Clinton (51.1% to 41.7%).
More: How is the Des Moines Register/Mediacom Iowa Poll conducted? We answer your top questions.
2012: Final Iowa Poll has Barack Obama ahead of Mitt Romney
President Barack Obama faced challenger Mitt Romney in 2012.
The final Des Moines Register/Mediacom Iowa Poll had Obama with a 5-point lead over Romney (47% to 42%).
On Election night, Obama carried the state by 6 points (52% to 46%).
2008: Barack Obama has a dominant lead over John McCain in final Iowa Poll
Iowa helped launch Barack Obama as a presidential candidate when he won the 2008 Iowa Caucuses.
Heading into Election Day, the final Iowa Poll looked like Obama would easily carry the state over challenger John McCain. The poll showed him with a 17-point lead (54% to 37%).
When the polls closed, Obama won the state by a narrower margin: 10 points. He earned 54% of the vote, but McCain got 44%.
2004: John Kerry has lead over President George W. Bush
Iowa was seen as a battleground state in 2004 after President George W. Bush was dogged by low job approval ratings. Iowa did not vote for Bush in 2000, instead picking former Vice President Al Gore.
The final Iowa Poll, showed U.S. Sen. John Kerry, the Democratic challenger, with a 5-point lead (48% to 43%).
On Election Night, Bush eked out a narrow win getting 49.9% of the vote compared with Kerry’s 49.2%. Bush was the first Republican to win the state since Ronald Reagan in 1984.
Brian Smith is the Register’s audience growth strategist. Reach him at bsmith@dmreg.com or 515-284-8214.
This article originally appeared on Des Moines Register: How do past Iowa Poll results compare with Iowa election results?
