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The race to Election Day in November is in high gear.

Former President Donald Trump and Vice President Kamala Harris squared off in a high-stakes debate in which Harris, arguably, got the upper hand.

They and their respective running mates now have limited time to convince the few undecided voters and make sure everyone in key battleground states gets to the polls.

Some voters are starting to cast ballots, but there will be unexpected developments between now and Election Day on November 5.

Nobody expected President Joe Biden’s campaign to implode after theshock of his performance at CNN’s debate in late June. Democrats went from literally freaking out about his candidacy to a new excitement about Harris as his replacement.

Nobody expected an assassination attempt against Trump, an event that unified Republicans around him and has many in his party showing a sort of divine reverence for his near-death experience.

So we don’t know specifically what will happen between now andElection Day, or what could come after, when the country’s unique Electoral College process gets going. But we do have some idea of what to expect:

September: Early voting begins

Early voting gets underway in September. North Carolina was supposed to be the first state to send mail-in ballots, on September 6, but the process was delayed by courts that ruled that ballots must be reprinted to remove Robert F. Kennedy Jr.’s name. Kennedy suspended his independent presidential bid in August and endorsed Trump.

Absentee ballots have started going out in Alabama, and other states begin sending mail-in ballots later in the month. Voters in most of the country have the option of requesting a mail-in ballot, and voters in eight of those states and Washington, DC, will get a mail-in ballot automatically. The other states require an excuse for mail-in ballots.

Back in school and back to work, many Americans may start to pay more attention to the election in September. There will also be some touchstone moments in the cultural zeitgeist, such as when “Saturday Night Live” premiers at the end of the month with Maya Rudolph returning as Harris – and we find out who will play vice presidential nominees JD Vance and Tim Walz.

Trump was also set to face sentencing in September for his conviction on 34 counts of falsifying business records related to hush money payments before the 2016 election, but that has been delayed until after this year’s election. Separately, Trump’s federal trial for 2020 election interference was restarted after special counsel Jack Smith responded to the Supreme Court’s grant of heightened presidential immunity with a pared-back set of charges. But those proceedings could drag on for months.

October: Vice presidential debate

The month begins with a vice presidential debate between Vance and Walz on October 1, hosted by CBS.

While Election Day isn’t until November 5, most states allow some kind of early voting, either by mail or in person, and that process will kick into overdrive in October.

Most Americans, nearly 70%, voted early or by mail in 2020, according to census figures, although that figure was affected by the Covid-19 pandemic.

The campaigns will be focused on getting out the vote in the few key battleground states they think are up for grabs. In 2020, Biden won five states that Trump won in 2016. Those states – Arizona, Georgia, Michigan, Pennsylvania and Wisconsin – could again be the focus in 2024 when Harris, who turns 60 in October, takes on Trump.

It’s important to be sure you’re registered to vote by October, which can usually be done online. Twenty-three states and Washington, DC, allow Election Day voter registration.

November: Election Day and beyond

US law requires federal elections to take place on the Tuesday after the first Monday in November. This year, that’s November 5.

People who don’t vote early will hit their local voting location. Polls will close at different times around the country. Due to the rise of voting by mail, if key states are close, like they were in 2020, we probably won’t know the winner on Election Day.

Regardless, expect lawsuits in certain states and the potential for recounts in others. Election Day is far from the end of the election.

Separately, Trump’s sentencing on 34 counts of falsifying business records is now scheduled for November 26.

Also this month: Biden turns 82.

December: Electoral votes are cast

After questions about the election are settled, states confirm, or ascertain, their statewide results. Electors gather in their respective state capitols to cast electoral votes for their statewide winner.

Nebraska and Maine also allocate some electoral votes by congressional district, and these could be pivotal in a close race.

January: Someone will solemnly swear

The new Congress takes the oath of office on January 3. It’s this new Congress that, in the unlikely event of an Electoral College tie, would settle the election. Each state would get one vote for president in the House of Representatives.

In any event, lawmakers gather on January 6, as everyone should remember from 2020, to count electoral votes. Harris will preside. She could either be the fifth vice president in history to oversee her own Electoral College victory, or the fourth in history to oversee her own Electoral College defeat.

On January 20, 2025, the next president takes the oath of office.

This story has been updated with additional developments.