In the largest poll taken this election cycle, Vice President Harris has a comfortable lead over President Trump nationally, possibly putting her on track to mirror President Biden’s victory four years ago. The state-by-state polls have tightened significantly since early and mail voting began just weeks ago, however. 

The poll finds that Ms. Harris has a four-point lead over Trump in the national vote, 51 percent to 47 percent. Both candidates win 95 percent of their respective parties while losing four percent to the other nominee, while independents break for Trump by a three-point margin. 

The survey, Tufts University’s Cooperative Election Study, was conducted by YouGov over the course of three weeks beginning on October 1. It is the “largest academic survey focused on American elections,” according to CES. This year, pollsters talked to more than 78,000 Americans for their survey.

One poll analyst pointed out that the CES survey has — like other polls — underestimated Trump in the past.

“In 2020, the CES pre-election estimate nailed Biden’s nationwide percentage, while underestimating Trump by four,” wrote a contributor for DecisionDesk HQ, Nick Field, on X. That poll found Trump losing to Mr. Biden, 51 percent to 43 percent, while the 2016 CES survey underestimated both Senator Clinton and Trump, with Ms. Clinton taking 43 percent and Trump taking 39 percent in their pre-election survey, though they would go on to win 48 percent and 46 percent, respectively. 

Ms. Harris is leading Trump with key demographics that could help her win some, or all, of the seven battleground states up for grabs this year. Among survey respondents who did not vote in 2020, Ms. Harris is winning by nine points, 51 percent to 42 percent. 

Women are flocking to Ms. Harris in numbers previously unseen for any presidential nominee, helping to drive what could be the largest gender gap in voting preference in American history. According to the survey, Ms. Harris is winning the female vote — regardless of income, race, or educational attainment — by nine points. 

The education divide is even more stark, and could save Ms. Harris in critical suburbs around Atlanta, Philadelphia, Milwaukee, and Phoenix, among others. Ms. Harris leads Trump among white voters with a college degree by 17 points — nearly double the nine-point margin by which President Biden won the demographic four years ago.

Among all college-educated voters, Ms. Harris leads by 21 points. Fears about Ms. Harris’s struggles with young voters due to the Israel–Hamas war may be overstated, as this poll finds she is winning voters under 40 by 22 points, which is nearly identical to Mr. Biden’s 2020 victory among the group. 

Trump’s strength in the poll comes from a realignment of minority voters and those without college degrees. Despite winning just eight percent of the Black vote in 2020, the poll finds he is winning more than one in five Black voters this year. Trump is losing Hispanics by only 18 points, even though he lost them by 21 points in 2020. Among voters of all races without a college degree, Trump is winning by five points.

As Ms. Harris enters the final week of the campaign with an ever-so-slight lead in the national poll averages, voter turnout continues to hit new records as early votes and mail votes are processed. From Georgia to Wisconsin to New York, Americans are lining up in droves to cast their ballots. 

In Pennsylvania, arguably the most important state in this year’s election, Ms. Harris’s get-out-the-vote operation seems to be working. According to vote-by-mail data released by the secretary of state’s office on Monday, Democrats so far have hit a 70 percent return rate for all of those ballots that have been sent to voters so far. In years where Democrats have been successful statewide in Pennsylvania, they have hit around 90 percent in total mail returns before the polls close on election day. In total, registered Democrats have supplied around 820,000 of all votes cast in the state so far, which is about 60 percent. 

The other state where Ms. Harris is faring relatively well is Michigan, where the highest rates of return for ballots and the highest number of total votes counted have come from reliably blue areas like Detroit and Ann Arbor. Statewide, 25 percent of registered voters have cast ballots so far, which translates to about 1.5 million votes. 

Trump’s greatest triumphs with early and mail voting have been in Georgia and Florida, the former being another pivotal battleground state. In Georgia, Republicans and Democrats are tied in the number of votes returned so far, with both parties getting around 1.2 million ballots to election officials.

Ms. Harris’s biggest problem seems to be that turnout numbers are exceptionally low among voters under the age of 40, with that demographic representing only about 22 percent of returned ballots despite making up 40 percent of the state’s population.