The presidential race is competitive.

That's about as much as the national polls can tell us right now, even if it looks like Democrat Kamala Harris is down in one poll or Republican Donald Trump is up in another.

That's fine; though polls are sometimes treated as projections, they aren't designed to tell you who is likely to win.

Tracking shifts in voter intention is hard to do with a survey, particularly when the number of truly persuadable voters is relatively small. Voters' opinions can change before Election Day and often do.

Horse race polls can only capture people's viewpoints at a single moment in time. Even then, a margin that looks like one that could decide an election — say, one candidate has 48% support and the other has 45% support — might not be a real difference at all.

The Associated Press believes focusing on pre-election polling can overstate the significance or reliability of those numbers, so horse race polling numbers don’t take center stage in its coverage.

Election-year polls are still useful, particularly when they try to assess how the public feels about candidates or the state of the country. For instance, they told us many Americans wanted Democratic President Joe Biden to drop out of the 2024 race.

But polls are not the same thing as an election result. Even a poll conducted just before Election Day still reflects opinion before all ballots are cast.

A waitress wearing a face mask to help curb the spread of COVID-19 stands near a TV showing a live telecast of U.S. election results Nov. 4, 2020, at a pub in Beijing.

Just estimates

Polls are useful tools, but it's important not to overstate their accuracy. After all, a polling organization can't talk to every single person in the country. They rely on a sample to produce a statistically valid estimate of the views of all adults.

Though polls can give a reasonable approximation of the views of the larger group, the question is how much each finding could vary. The margin of error, which all high-quality pollsters will share with their results, helps capture some of that uncertainty.

In a poll with a margin of error of plus or minus 3 percentage points, a finding that 47% of voters say they'll support a particular candidate actually means there's a very good chance anywhere between 50% and 44% of voters support that candidate. If the other candidate has 45% support, which could really be anywhere from 42% to 48%, the 2 percentage point difference isn't statistically meaningful.

That's why the AP will only say a candidate is leading if that candidate is ahead by more than twice the margin of error.

The fewer people interviewed, the larger the margin of error. This means state-level polls or polls that measure the views of a subgroup such as women, men, Hispanic Americans or Black Americans are subject to even more error than a national finding.

The margin of sampling error is not the only source of survey error. It is simply the only one that can be quantified using established statistical methods.

There are other factors, too. The wording and order of questions can affect how people answer. An interviewer's skill can have an effect. Even in high-quality polls, some respondents may be less likely to answer, which means their views can be underrepresented.

Democratic presidential nominee Vice President Kamala Harris

Electoral College

National polls measure how voters all over the country are thinking about the election, but that's not how we elect presidents.

The Electoral College system means presidential elections are functionally decided by a small number of states. So in some ways, looking at polls of those states is a better way to assess the state of the race.

State-level polls have their own challenges. They're not conducted as frequently as national polls and some states get polled more often than others.

The number of people surveyed for state polls is often smaller than for national polls, which means the margin of error is broader.

Republican presidential nominee former President Donald Trump

Averaging results

Some media outlets or organizations publish polling averages or aggregates that combine the results of multiple polls into a single estimate. Some organizations create polling averages or models that attempt to determine which candidate is leading in overall polls.

Averaging poll results does not eliminate polling error and it can introduce additional problems. Polling averages contain their own methodological decisions, such as which polls are included or receive greater weight. Some also include other factors, such as the state of the economy, to turn estimates into forecasts.

While survey averages can provide a general sense of the state of a race, it's important to not overstate the accuracy of an average or expect it to be a crystal ball into an election outcome.

Sometimes individual results of multiple different polls can provide a better sense of the potential array of outcomes than an average boiled down to a single number.

Explaining Election Day: Understanding the processes from voting to declaring winners

The Associated Press has created a series of videos explaining how elections work in the United States.


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