Get ready for a long election night — or nights.

The 2024 presidential race is likely to come down to the seven battleground states: Arizona, Georgia, Michigan, Nevada, North Carolina, Pennsylvania and Wisconsin. Winners are most likely to be called in Georgia, Michigan and North Carolina, but in the other four it may take some time, especially if the margins are close. In fact, thanks to a combination of new state laws and the inaction of legislators who could have made vote-counting more efficient — but didn’t — it may take even longer to declare a winner than it did in 2020, when news organizations called the race four days after Election Day.

A long lag between Election Day and the announcement of a winner would test the country. In 2020, misinformation and conspiracy theories flourished as vote counting dragged on in a handful of key battleground states. So for this Election Day it is critical that people know what to expect, the true nature of the likely delays and how some of them might have been prevented.

Since 2020, Arizona, Nevada, Pennsylvania and Wisconsin have either added rules that could slow down their vote counts, or allowed existing rules that contributed to long tabulating times in 2020 to remain in place. Only Michigan and North Carolina have meaningfully changed their laws to speed up the process. (Fortunately, Georgia historically counts quickly; Trump-aligned members of the state election board recently tried to impose rules that would have slowed the process down, but Georgia’s courts rejected the attempt.)

The result is a patchwork of new developments and old laws — a few of which are encouraging, but many of which are troubling. It’s a recipe for delays and confusion if the race is close.

Results are never official on election night, but media outlets and campaigns release partial vote totals and declare winners when they think enough ballots have been counted and the margins are large enough to make a determination. The official certification comes days or weeks later.

One important thing to keep in mind this November is that the release of partial vote totals may lead to a repeat of the “red mirage” or “blue shift” phenomenon of 2020. Because Democrats have historically made heavier use of mail ballots, Republicans often appear to do better on Election Day, whereas Democrats can appear to surge in the days after the election as mail ballots are tabulated. Still unclear is whether a Republican push this year to have their voters cast ballots early will change this pattern.