Pennsylvania is poised to face many of the same challenges in 2024 that it experienced in the 2020 election which led to the state not being called for President Joe Biden until days after Election Day.

The dayslong delay in determining the winner sparked widespread accusations of voter fraud in Pennsylvania, leading to the Keystone State being among the battleground states that faced lawsuits from former President Donald Trump’s campaign in 2020. Four years later, state legislators have failed to resolve the key disputes over ballot tabulation and certification that prompted the backlog.

Pennsylvania has established itself as the cornerstone of the 2024 election, with its 19 electoral votes and battleground status making it among the biggest prizes on election night and crucial to winning the presidency. The state was paramount to Trump’s victory in 2016 as well as Biden’s in 2020, prompting both parties to pour millions of dollars into the state to secure a pathway to the White House.

Some changes have been made in the state since 2020, such as a lower court ruling last week that would require counties to notify voters if their ballots are at risk of being rejected. Another ruling passed down last week would overturn a state requirement to throw out ballots if they are not correctly dated.

However, several other disputes await rulings from Pennsylvania judges, which could alter the state of play for vote counting in a key swing state.

And even as some of those legal challenges are being worked out, Pennsylvania remains one of only two states that have not passed any sort of expansive, restrictive, or interference-related law since the 2020 election, according to the Brennan Center for Justice.

Here’s everything you need to know about how Pennsylvania conducts its elections as well as the legal challenges that could change the game ahead of Nov. 5.

Procedural changes and pending legal challenges

Although there have not been any comprehensive changes to Pennsylvania’s election laws over the last four years, there have been a handful of lower court rulings that could have major implications in November. 

One of the key changes was handed down last week when the Commonwealth Court ruled that it was unconstitutional to enforce a state law requiring accurate, handwritten dates on mail-in ballots in order to be tallied. The ruling will allow the state to count “undated or incorrectly dated” ballots that were submitted before the deadline. 

“The refusal to count undated or incorrectly dated but timely mail ballots submitted by otherwise eligible voters because of meaningless and inconsequential paperwork errors violates the fundamental right to vote,” wrote Judge Ellen Ceisler in the majority opinion. 

The ruling, if left standing, is likely to salvage thousands of ballots that would have otherwise been thrown out. Tom King, who represents the state and national Republican Party groups involved in the case, said he “absolutely will appeal.” 

Judges in Washington County also approved a lawsuit on Friday that would require county officials to notify voters if their mail-in ballots are at risk of being rejected, giving them the opportunity to either challenge the decision or cast a provisional ballot instead.

Pennsylvania lawmakers sought to make other procedural changes by introducing legislation to establish same-day voter registration, expand early voting, impose new voter ID requirements, and more. However, due to political gridlock in the state legislature, no new bills have been passed. 

When does voting begin? 

Pennsylvania voters can submit their ballots either in person at their respective polling locations across the state, or they can vote by mail in the weeks leading up to Election Day. 

Pennsylvania is one of 10 states to send ballots more than 45 days before the election, meaning the first round of ballots will be sent to voters beginning Friday. That first batch is typically sent to those in the military or serving overseas. 

Beginning Sept. 16, all voters can visit their local election office to request a mail-in ballot and submit it as soon as they prefer. To be approved for a mail-in ballot, voters are required to provide a valid driver’s license number or the last four digits of their Social Security number on the absentee or mail-in ballot form.

The last day to request a mail-in ballot is Oct. 29. Absentee ballots that are mailed or dropped off at polling locations must be received by election officials before 8 p.m. on Election Day. 

For those voting in person on Election Day, polls open at 7 a.m. and close at 8 p.m. Anyone who is in line by 8 p.m. is eligible to vote even if polls close before they cast their ballot. 

Once at the polling place, voters must check in with poll workers before either being handed a paper ballot or casting their vote using a machine called a ballot marking device. The method varies by polling station. 

When can the state start counting ballots? 

One administrative hurdle that emerged as a key contention in the 2020 election was the state’s lack of preprocessing and precanvassing for absentee ballots — something that has still not been resolved ahead of November. 

Pennsylvania law prohibits election workers from opening mail-in ballots until 7 a.m. on Election Day. As a result, poll workers cannot begin sorting through the thousands of ballots received in the weeks leading up to Election Day. 

That obstacle is what caused the state to experience a backlog during the 2020 election and prompted widespread accusations of voter fraud that led to Biden’s victory. 

When the polls closed in Pennsylvania on Election Day in 2020, the initial count of in-person ballots appeared to show Trump ahead. But as the state began to tally mail-in ballots over the coming days, that lead began to disappear. By that Saturday, the state was called in favor of Biden, pushing him past the 270-electoral vote threshold and securing the presidency. 

State lawmakers sought to change that rule earlier this year, with the state House passing a bill along party lines that would have allowed officials to begin canvassing mail-in ballots one week before Election Day. However, that bill was blocked by the Republican-controlled Senate, which never brought it to the floor for a vote. 

So, how long will it take to know the results? 

Because that bill didn’t pass the state legislature, it’s likely to be days before ballots are counted and results are certified in Pennsylvania. 

What are poll watchers and what rules must they follow? 

Every polling location has poll watchers assigned to the ballot counting site by individual campaigns and political parties. 

In Pennsylvania, candidates may assign up to two poll watchers per location while political parties may appoint up to three. However, only one poll watcher may be present in the counting site at one time for each candidate and political party. 

State law requires poll watchers to be a registered voter of the county where they’ll be carrying out their assignment. Each watcher must also obtain a certificate from their county board of elections that states their name as well as the name of the candidate or political party they represent. Watchers are required to present this certificate to election officials if requested. 

Watchers are permitted to stay in the polling place after polls close at 8 p.m., but they are not allowed to enter the space where ballots are being counted. Poll watchers may also keep a list of voters and view the official voter list, so long as it is under the supervision of a poll worker and no voters are present in the polling place. 

Poll watchers may file challenges to a voter’s identity or residence but only if they present evidence to the judge of elections. Challenges may not be made based on one’s race, religion, language, appearance, national origin, or name. 

Poll watchers are prohibited from conducting campaign-related activities inside or within 10 feet of a polling place, threatening or intimidating voters, marking election records, or entering the enclosed space where ballots are being counted. 

What counties are likely to determine the outcome? 

Although the election is decided by a handful of battleground states, there are some counties that hold more weight than others when it comes to clinching the states’ electoral votes. 

At least two of those counties are in Pennsylvania: Erie and Lackawanna. 

Erie County, located in the northwestern corner of the state, is often considered the bellwether county of an otherwise bellwether state — where it leans, the rest of the state is likely to mirror. 

In the 25 statewide elections since 2008 — including those for president, senator, governor, attorney general, treasurer, and auditor — Erie County has voted for the winner more than 90% of the time.

But the county is also known for swinging back and forth between Democrats and Republicans, voting for 20 Democratic candidates and five Republicans during that time. Trump won the county by 1.5 points in the 2016 election before losing it to Biden by 1 point in 2020. 

On the opposite side of the state lies Lackawanna County, a historically Democratic county that has trended toward Republicans in recent years. Although the county has not gone so far as to vote for a GOP presidential nominee in the last several presidential cycles, the margin has gotten more narrow over the last two decades. 

Between 2000 and 2012, the Democratic nominee received between 56% and 63% of the presidential vote in the county. In 2016, Hillary Clinton’s support fell below 50% and she defeated Trump by only 3.5 points in Lackawanna.

What happens after the ballots are counted? 

Under state law, Pennsylvania counties are not permitted to record or publish mail ballot results until after the polls close at 8 p.m. on Election Day. 

Races are typically called by national news outlets such as the Associated Press even before all ballots have been counted. The Associated Press will call a race in one candidate’s favor when “the trailing candidates no longer have a path to victory,” according to the outlet. 

When the outlet calls the race, it provides “research and analysis that led us to say with certainty who has won.”

After every general election in Pennsylvania, all counties must conduct two separate and distinct types of audits. 

First, officials must conduct a 2% statistical recount that pulls a random sample of either 2% of all ballots cast in all races or a random sample of 2,000 ballots — whichever contains fewer ballots. 

Next, counties will conduct a statewide risk-limiting audit that examines a random sample of paper ballots to compare with the totals being reported by vote-counting machines. That way, officials can ensure the voting systems tabulated the paper ballots accurately. 

State law requires an automatic recount when the margin is less than or equal to 0.5% of the total vote. That recount must be requested by the secretary of state no later than 5 p.m. on the second Thursday following the election. It must then be completed by the following Wednesday.

A recount can also be requested within five days of the election with no margin required. Three voters of an election district may submit an affidavit alleging errors in the vote totals while paying for the cost of a recount themselves. If any errors or fraud are found, that cost will be refunded. 

There is no deadline by which that recount must be completed.

Who is on the ballot? 

There are four presidential tickets on the 2024 ballot in Pennsylvania: Vice President Kamala Harris and Gov. Tim Walz (D-MN) for the Democratic Party; Trump and Sen. J.D. Vance (R-OH) for the Republican Party; Jill Stein and Samson LeBeau Kpadenou for the Green Party; and Chase Oliver and Mike ter Maat for the Libertarian Party. 

Notably, Robert F. Kennedy Jr. will be absent from the ballot after a judge approved his request to remove his name from the ballot. Kennedy suspended his campaign last month and endorsed Trump. 

Without his name possibly serving as a “spoiler,” that could make the race all the more closer for Harris and Trump. Recent polling shows the two tied at 47% in Pennsylvania, making it one of the most important battleground states come November.