Those who were there have not forgotten it.On election night, November 8, 2016, after months in which countless polls had all but crowned Hillary Clinton the clear winner, the states of Pennsylvania, Michigan and Wisconsin, long considered safely Democratic by pollsters, fell one after another to Republican Donald Trump, handing him the presidency.
Although Clinton won the popular vote, the polls had missed the mark spectacularly, and the outcome caught much of U.S. society, the media and the political establishment by surprise. In the aftermath came a litany of postmortems and mea culpas from the U.S. polling industry, which admitted it had failed to grasp the mood of the elusive Trump voter.
Now, a decade after that statistical debacle, polls are forecasting a so-called “blue wave” in the November 3 midterm elections. In surveys measuring the generic congressional ballot, Democrats lead Republicans by eight points. That is roughly the same margin they held in 2018, when they regained control of the House of Representatives with a net gain of 41 seats. Democrats therefore have plenty of reason to feel optimistic about their chances of winning it back again.
Things also look promising for the Democrats in the Senate. Democratic candidates are leading in states that Trump won comfortably in 2024, including Texas, Ohio, Iowa and Alaska. But their advantage in those races is so small that it falls within the margin of error.
And on the eve of an election, experts say, it is worth remembering that a poll is only an estimate and that a small statistical miss could turn a potential “blue wave” either into an electoral tsunami that hands Democrats both chambers of Congress or into little more than a ripple that gives them control of the House of Representatives alone.
How large are polling errors?
In the last five midterm elections, the final polling average missed the actual result by between 0.2 and 3.5 percentage points. An error of two or three points may seem small, but what matters is that polling errors are rarely random, explains Charles Franklin, a prominent pollster who heads the respected Marquette Law School Poll in Wisconsin.
When polls miss the mark, they tend to do so in the same direction across the country. In other words, if polls are currently underestimating Republicans in the Senate race in Texas, they are likely doing the same in Ohio and Iowa. That is why a single polling bias can decide several races at once, benefiting the same party. “Most of those battleground states end up all moving in the Republican direction or all moving in the Democratic direction,” explains Franklin.
Several recent elections illustrate this cascading effect. In the 2006 and 2014 midterms, polls overestimated Democratic support; in 2010 and 2018, they overestimated Republicans. The same pattern has appeared in presidential elections: polls underestimated Barack Obama in 2012 and Trump in 2016, 2020 and 2024.
The chart below shows how those polling misses have played out across recent election cycles.
Why does this happen? One reason a “wave” can become a tsunami or fizzle out in the midterms is that local races are closely tied to national political forces, which act like a prevailing current, explains Charles Franklin.
“Presidential approval, the state of the economy, how you feel about the war with Iran… those national forces push all those races in one direction,” he says. That is why, if polls misjudge the national mood, the bias tends to be repeated across multiple contests.
This time, those “national forces” appear to be hurting Trump’s party. His approval ratings are at historic lows because of inflation, gasoline prices and broader economic concerns. It is even possible, Franklin says, that this anti-Trump sentiment is being overrepresented in polls. He warns that pollsters may be picking up “too many” Democrats who are “happy to take a survey and tell you how much they dislike the president.”
What to expect in the House of Representatives?
The two chambers of Congress do not respond in the same way to polling swings.
In the House of Representatives, the Democratic lead on the generic ballot is so large and so consistent that Republicans could only hold on to their current majority if polling errors exceeded those seen in any of the last nine elections.
At this stage, Franklin says, the real question is not whether Democrats will win the House, but by how much. If the polls are overstating Democratic support and the party gains fewer than 15 seats, election night will be “disappointing.” A gain of 15 to 20 seats would be “plausible”; 20 to 25 would be “pretty good”; and a sweep of 30 seats or more would amount to “a great night.”
And in the Senate?
Here, Republicans begin with an advantage. Of the 65 senators who are not up for reelection this year, 31 are Republicans and, in the event of a 50-50 tie, the deciding vote belongs to Vice President J. D. Vance.
Several competitive races are being decided by margins of less than three percentage points, and an error of the kind seen in the 2014 midterms or the 2020 presidential election would be enough for Republicans to retain control of the upper chamber.
Again, everything depends on the direction of any polling bias, Franklin says. If the polls have overestimated Democratic support, particularly in traditionally Republican states such as Texas and Kansas, then by the morning of November 4 we could find that Trump’s party has held on to the Senate. If, on the other hand, the polls are underestimating Democrats, they could also capture the upper chamber, potentially ending up with a majority of 52 or 53 seats. Both scenarios, though opposite, are plausible.
There are precedents for that as well. In the 2012 presidential election, for example, polls underestimated Obama by more than three percentage points.
If Democrats outperform their polling numbers by a similar margin this year, the wave really could become a tsunami. The Democrats would win districts that Trump carried by more than 10 points and put states such as Kansas, South Carolina and Mississippi into play, conservative strongholds that should not, in theory, be giving Republicans headaches. Yet Trump has been forced to campaign in them precisely because of his party’s weak polling numbers there.
How to read the polls with caution
None of these scenarios should be interpreted as a prediction, Franklin says. Recent history suggests that the real question is not whether polls will be wrong, but by how much and in which direction. Polling errors can vary from state to state, and calculations like these do not account for the individual strengths of incumbents or the personal appeal of specific candidates.
Faced with the daily flood of polling averages, Franklin advises against treating polls as crystal balls, “unless you happen to know a good witch in your neighborhood,” he jokes. Rather than focusing solely on whether a candidate leads by one or two points, a razor-thin margin, he recommends paying attention to the spread of the data. When polls in the same state point in different directions, with some showing one party ahead and others favoring its rival, the only firm conclusion is uncertainty.
His recommendation on the eve of the elections? “Be uncertain.”
A dozen cancer patients have gathered at the Smokey Row café in Ankeny, a prosperous suburb north of Des Moines. They have come to share their experiences with Rob Sand, the charismatic Democratic candidate for governor of Iowa, a Midwestern state known for its endless cornfields. It is one of the emblematic territories of the so-called Corn Belt, the agricultural heartland of the United States, which overwhelmingly backed Donald Trump in the 2024 election. The Democrats are pinning their hopes on Sand. He is slightly ahead in the polls over his conservative rival, Zach Lahn. He is on the verge of becoming the first Democrat to win a major statewide election in Iowa in nearly two decades.
The Democrats’ other leading contender for breaking through in rural America is Josh Turek, a 47-year-old three-time Paralympic basketball medalist. He has used a wheelchair since childhood. He is running for Iowa’s U.S. Senate seat, which has been in Republican hands for 18 years. He is tied in the polls with Republican Ashley Hinson, a former local television presenter. Hinson is young, blonde and has stronger debating skills than Turek, as she demonstrated in the two televised debates. But Turek is steady, persistent and projects an image of resilience and perseverance that draws voters’ interest.
A week spent roaming Des Moines and Cedar Rapids, Iowa’s two largest cities, is enough to realize that the issue weighing most heavily on voters’ minds is water quality. Many wonder whether it has been contaminated by runoff from agricultural chemicals such as fertilizers, pesticides and nitrates. Cancer rates in the state have risen alarmingly in recent years, and many point to the water as a possible cause. The concern surfaces in conversation after conversation. Iowa has the country’s second-highest increase in cancer cases among young adults.
Rob Sand, wearing gray New Balance sneakers and a dark shirt untucked over beige trousers, as if he were a college student, listens patiently as each attendee shares their story at an event attended by EL PAÍS in mid-October. Among them is Isabelle Ireland, who has travelled 37 miles from Saint Marys, to explain that she was diagnosed at 16 with an extraordinarily rare form of cancer and treated with the same chemotherapy that was being used 50 years ago.
Sand asks questions, takes an interest in the details of each case and, above all, avoids making empty promises. He does not deliver a long, grandiose speech: he only pledges to focus the administration’s efforts on patients rather than bureaucracy.
From ‘Vogue Italia’ to hunting a bison
Rob Sand stands around 6 ft 3 in tall. He is 44, with light brown hair, blue eyes and the face of Tom Sawyer. No one would guess that this moderate Midwestern politician, who enjoys bow hunting and keeps a bison head mounted in his office, once worked as a model on the runways of Milan and Paris.
As a young man, he had the languid, carefree look favored by fashion magazines such as Vogue Italia. He even posed for photographers including Terry Richardson, but it is not something he likes to be remembered for. That chapter is behind him. Today, he cultivates the image of an ordinary Iowan concerned with the everyday problems of his neighbors. That is why he is in a café in Ankeny.
Sand is not a conventional politician. Despite his relaxed appearance, he often seems like a man from another era: somewhat moralistic, religious, teetotal and moderate. He opens his rallies with America the Beautiful, one of Donald Trump’s favorite songs; likes to weave Christian references into his speeches; and criticizes political polarization. He describes the two major parties as “private clubs.” He has a particular knack for steering clear of controversial issues and avoiding hot-button disputes.
Some say he bears a certain resemblance to John F. Kennedy. The Wall Street Journal described him as “the Democrat who Republicans fear in red-state America.”
Sand is married to Christine Lauridsen, the chief executive of a company that produces additives for broths and pet food. They have two children. His wife comes from a wealthy family that has financed much of his political career.
Originally from Decorah, a forested area in the state’s northeast, Sand is the son of a doctor and a physiotherapist who worked with children with disabilities. He earned a degree in Political Science from Brown University in Rhode Island, where he attended on a scholarship and wrote a thesis on political participation. After graduating, he spent some time in Europe working as a model. Upon returning to Iowa, he completed a law degree at the state’s university. He often boasts that he turned down Harvard to stay in Iowa, known as the United States’ largest agricultural producer.
He worked for several years as an aide to the state attorney general before running for the elected post of state auditor. His victory drew the attention of the Democratic Party. Since then, he has received numerous endorsements for his ability to win elections in deeply conservative territory.
His experience as auditor has left its mark. He seems almost obsessed with efficiency, repeatedly stressing the need to ensure that every public dollar is spent effectively and not lost to irregularities or bureaucratic waste.
Turek, the image of perseverance
In addition to water quality, Iowa voters are worried about the economy. In recent years, discontent has been growing among the state’s influential farmers. That is where Josh Turek comes in. Seated in his aluminium wheelchair atop a carbon-fibre frame, he has travelled to all 99 counties in Iowa, explaining the impact that tariffs and the war with Iran have had on the region’s economy.
Turek is challenging Ashley Hinson for Iowa’s U.S. Senate seat in a state that Donald Trump carried by more than 13 percentage points two years ago. But he thrives on competition. He has spent his entire life fighting.
Turek was born with spina bifida as a result of his father’s exposure to chemical agents during the Vietnam War. He had already undergone 21 surgical operations by the time he was 10. He has used a wheelchair ever since. But that has never stopped him from taking on challenges.
When he saw his younger brothers playing basketball beside the porch of their home, he wanted to join them. At 12, he attended a camp for people with mobility disabilities. What began as a hobby became a way of life.
He went on to become a standout athlete at the University of Minnesota, where he captained the team. In late 2004, he moved to Spain to play for Fundosa ONCE, one of the top teams in the Spanish league, where he became a star. He later signed for a team in Bilbao. Altogether, he spent nearly a decade playing for various clubs in Spain’s wheelchair basketball league, where he met his wife, who is of Dominican origin.
Since 2022, when he won election to the state legislature, he has served as a lawmaker in Des Moines. He often highlights the dozens of times he has worked across party lines with Republicans on issues such as tougher penalties for repeat offenders among immigrants and public safety measures.
Basketball star in Spain
Turek is from Council Bluffs, a small town in the state’s southwest, and was raised in a humble household. His father, an Army veteran, carried the grief throughout his life of losing his first daughter, who drowned in a swimming pool. His mother worked as a social worker for people with intellectual disabilities.
“It’s hard enough to grow up in poverty, but it’s really tough to grow up poor and disabled,” he said at one rally, where he acknowledged he suffered bullying because of his mobility issues. “I didn’t have many friends, I had low self-esteem, and basketball and adaptive sports gave me an escape,” he said.
He retired from professional basketball in 2022 with an impressive record: two gold medals at the Paralympic Games in Rio (2016) and Tokyo (2021), after winning bronze in London.
He returned to Iowa to work for a mobility-device company. His leap into politics came after he grew frustrated seeing how many medical requests for children with disabilities were denied. He ran for the state House and won his seat by six votes. He describes himself as “a prairie populist” and, while he holds progressive views, he has emphasized his moderate credentials on the campaign trail to counter attacks from his opponent. Hinson argues that he is too liberal for Iowa.
The candidate has secured the endorsement of Barack Obama, who recorded a campaign video playing basketball with Turek. “He’s someone who knows how to win,” the former Democratic president said.
During the two televised debates between Turek and Hinson, the Republican demonstrated a quicker ability to respond on her feet than the former athlete, who at times appeared uncomfortable, pausing to drink water as his mouth went dry. Still, he held his own by repeatedly attacking the conservative congresswoman, accusing her of excessive loyalty to Trump and of backing the tariffs, the war with Iran and the Big Beautiful Bill, which has cut healthcare coverage for thousands of Americans.
Hinson accuses him of frequently being absent from his office and skipping sessions of the state legislature. He counters that he has chosen instead to spend time out in the field with voters. Unlike his opponent, Turek does not stand out for his physical presence or his debating skills. But local residents describe him as reliable, persistent and genuinely committed to the community. Polls suggest he has a real chance of wresting the seat from the Republicans. To do so, he will need to sink one final basket.
Sign up for our weekly newsletter to get more English-language news coverage from EL PAÍS USA Edition
Se ha hecho esperar, pero al final ha dado el paso. Barack Obama, el presidente demócrata más popular de este siglo, se remangó la camisa para participar en dos actos en el mismo día: en Cleveland (Ohio) y en Detroit (Michigan) en sus primeros mitines de la campaña para las elecciones de medio mandato, que se celebran en apenas 10 días. Obama es todo un símbolo entre las filas demócratas. El presidente de la esperanza, el del verbo ágil y retórica consumada, el que buscó la unión del pueblo estadounidense, arremetió con dureza contra lo que calificó como crueldad e indecencia del presidente Donald Trump y sus aliados republicanos. Y se mostró optimista con el futuro del país: “Se respira un aire de cambio”, dijo ante una audiencia entusiasmada. “Llevo mucho tiempo en esto y puedo decirles cuándo llegan unas elecciones que se sienten un poco diferentes, donde la gente está tan preparada para algo nuevo, tan ansiosa por algo mejor, tan harta de estar harta, que a dondequiera que vayas se respira un aire de cambio”.