When election night rolls around, all eyes will be on the results, but in close elections, it could be days before a projection is made.

In 2020, Joe Biden wasn't declared the winner of the presidential race until the Saturday after the election. In 2016, it wasn't nearly as close. Donald Trump was declared the winner early Wednesday morning. In 2012, the call came even earlier. President Barack Obama won his reelection contest before midnight on Election Day.

Pennsylvania, with 19 electoral votes, could be a state that decides the 2024 presidential election.

Cautioning that immediate election results are unofficial, Lamont McClure, an election official in Northampton County, Pennsylvania, told Scripps news that they intend to have all the votes from Election Day by 1 a.m. or 2 a.m.

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If the rest of Pennsylvania adheres to that timeline, it may be possible to project who will win the state, early Wednesday morning. However, whether Pennsylvania is the state that tips the scales in one candidate's favor will depend on how they do in the other battleground states.

There are seven battleground states, including Pennsylvania, Georgia, North Carolina, Michigan, Wisconsin, Nevada and Arizona.

In 2016, six of the seven states voted for Donald Trump. In 2020, six of the seven states voted for Joe Biden.

Each state has different rules for how and when they count ballots. For example, in Florida, election officials have already tabulated the ballots that early voters have already turned in. In Pennsylvania, officials must wait until Tuesday to even open mail-in ballots. In Georgia, all early votes must be counted and reported by 8 p.m. on election night.

Rachael Dean Wilson, managing director of the Alliance Defending Democracy, doesn't anticipate a quick result.

"The suspected margins of this race are going to be so tight," she said. "There is still going to be the potential for this to take a couple of days for us to know who won the election."

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