Unless polls predicting a razor-thin margin between Vice President Kamala Harris and former President Trump are completely wrong — a possibility due to staggering changes in the way voters cast their ballots and a pandemic-induced overhaul of election laws — Americans should plan are to continue. went to bed on Tuesday night without knowing who won the White House.

Election experts say a delay in knowing the results, partly because of the patchwork of rules dictating how votes are counted, especially in battleground states, is a testament to the vigilance of tellers in accurately tallying votes. But they also worry that any delay will fuel many Americans’ growing skepticism about the sanctity of the country’s electoral process.

“People are used to turning on their TV late on election night and seeing a winner splash across the screen,” said Jessica Levinson, an election law professor at Loyola Law School. “I think that’s largely a thing of the past. It’s hard to imagine how that could happen in a race that’s so close.”

She pointed to changing behavior among voters regarding how they cast their ballots, as well as differing rules about when mail-in ballots can be counted and how late ballots postmarked by Election Day are accepted. But she also worries that election officials’ efforts to accurately count votes will be misinterpreted as opportunities for fraud in today’s polarized climate.

“Everyone knows what a photo finish is,” Levinson said. Expecting a clear result on election night “is a bit like declaring victory before you can develop the film. Or it’s like declaring victory before you do the last lap, because honestly, the last lap counts.”

Charles Stewart III, the director of the MIT Election Data and Science Lab, said it will ultimately come down to the margin of victory in the race.

“In all of these states, part of the answer depends on how close the election actually is,” he said. “I say that because it really only matters when the elections are really close.”

More than 76 million Americans have voted since Sunday, either through mail-in ballots or in-person early voting, according to a tracker from the University of Florida’s Election Lab. Several states have reported record-breaking early returns, including two that could tilt the presidential race: Georgia and North Carolina.

According to the Minister of Foreign Affairs, more than four million Georgians had cast their votes on Friday. The number far exceeds the previous elections.

“Georgia voters know we’ve made it easy to vote. It really is that simple,” Secretary of State Brad Raffensperger, who famously opposed Trump’s efforts to increase his vote count in Georgia in 2020, said in a statement.

Some states have changed voting rules due to the pandemic, including California, which is now sending ballots to every registered voter, or in the wake of the controversial 2020 election. That includes some of the battleground states that will determine who is elected president . Additionally, some of these states have restrictions on when mail-in ballots can be received or counted.

In 2020, then-President Trump spoke out against mail-in ballots — historically a voting practice favored by Republicans. The end result was that voters saw candidates who appeared to be in the lead after the polls closed on Election Day lose once all the votes were counted. This led to widespread and false conspiracy theories in states like Michigan about the wavering vote count.

If Tuesday’s elections are as close, this scenario is likely to repeat itself.

“If the race in a key state comes down to a few thousand ballots, it could be days or weeks before we know the winner of the presidential election,” said Rachel Orey, director of the Bipartisan Policy Center’s Elections Project. “It really comes down to the margin of victory.”

Rick Hasen, a professor of campaign finance law at UCLA whose latest book is “A Real Right to Vote: How a Constitutional Amendment Can Safeguard American Democracy,” said the rules in Pennsylvania, Wisconsin, Nevada and Arizona could hinder the election of a winner . in particularly close elections.

“When it comes to these states, there could be a delay of a few days for various reasons,” Hasen said. “Pennsylvania and Wisconsin do not allow the processing of absentee ballots before Election Day. Wisconsin is moving faster because it is smaller, but the bottleneck is Milwaukee.”

“Nevada is a different problem, they allow ballots to arrive for four days” if they are postmarked by Election Day, he said. “And in Arizona they just have a lot of mail-in ballots, and it takes a very long time, just like in California.”

Another complication in Arizona is that voters in Maricopa County, the state’s most populous, will be asked to complete the longest round of voting they’ve seen in nearly two decades, Orey said. That could lead to delays at voting centers as voters take longer to cast their votes, delay tabulation and possibly cause paper jams in counting machines because the ballot consists of two pages, front and back.

However, there are bright spots in other key states, he said. Georgia and North Carolina are counting votes relatively quickly, and Michigan has changed its rules and will likely do so more quickly than four years ago.

A key question is whether elections in one state produce a small number of votes, like what happened in the 2000 race between Al Gore and George W. Bush.

“If it comes down to a few hundred or a few thousand votes in one state, it could take weeks,” Hasen said, noting that the chances of a repeat of that highly controversial election ultimately decided by the Supreme Court are slim . but not impossible. “Then all bets are off… It will be a ballot-to-ballot battle, of trench warfare.”

Stewart added that both Harris and Trump’s campaigns have prepared for this possibility.

“They’re loaded as bears, as they say,” he said. “Hundreds of lawyers and hundreds of files are ready to go.”

Hasen’s advice to concerned voters: Once the polls close Tuesday, recognize that delays in learning the results are a sign the system is working, and stay calm.

On Tuesday evening: “Everyone needs to take a breath, have some patience, have a glass of wine and get up the next day and do it all again,” he said. “Maybe we’ll know what the answer is by the end of the week. Unless it’s a blowout.”