US elections 2024: When will we know who won between Harris and Trump?

Americans are voting for their next president in a general election that ends on Tuesday, November 5.

Once the polling stations close, it is possible, depending on the importance of the competition, that the winner will not be chosen for several hours, several days, or even several weeks. Here's what you need to know.

Democrat Kamala Harris, the current vice president, and Republican Donald Trump, the former president, have been neck and neck for weeks.

National and swing state polls have tightened as November 5 approaches, so margins of victory could be very narrow in many places, potentially necessitating a recount.

It's also possible that some results will be released more slowly this year because of changes in how states — including the seven key states that will ultimately decide the race — have handled their elections since 2020.

On the other hand, counting has been accelerated in states like Michigan, and the number of postal votes will be much lower than in the last election, which took place during the avian flu pandemic.

This means that any number of outcomes are possible – a winner declared on election night, the next morning or perhaps days or weeks later.

The 2020 election took place on Tuesday, November 3, but American television networks did not declare Joe Biden the winner until late morning on Saturday, November 7.

As Americans went to bed on election night, Donald Trump supporters thought victory was close, but in fact both candidates were within reach of the 270 Electoral College votes needed to become president-elect.

Although the vast majority of states announced their results within 24 hours, a handful of key states, including Pennsylvania and Nevada, did not.

Pennsylvania, with its 19 electoral votes, nevertheless tended to lean towards the Democrats. On the morning of Saturday, November 7, a new batch of ballots counted in this key state allowed television networks to predict Joe Biden's victory in this state.

CNN was the first to announce the result, followed by every other television channel within 15 minutes.

In general, voters have become accustomed to the idea that they will know who the next president will be by the time they go to bed, late on election night, or at least in the early morning hours of the next day.

In 2016, for example, when Trump first won the presidency, he was declared the winner shortly before 3:00 a.m. EST (08:00 GMT) the day after the election.

In 2012, when Barack Obama won a second term, his victory was announced before midnight on Election Day itself.

The 2000 election between George W. Bush and Al Gore is a notable recent exception.

The two campaigns faced off in a close race in Florida, and the race was not decided until December 12, when the United States Supreme Court ruled to end the vote recount process in the state, keeping Bush in place as the certified winner and thus handing him the keys to the White House.

Across the country, the first polling stations will close at 6 p.m. EST (10 p.m. GMT) Tuesday evening and the last 1 a.m. EST (5 a.m. GMT) Wednesday early in the day.

But this race should come down to the results of the seven key states – Arizona, Georgia, Michigan, Nevada, North Carolina, Pennsylvania and Wisconsin.

19:00 EST (23:00 GMT) – Polls close in Georgia and five other states, and partially in two other states. That's also when U.S. TV networks will likely start making their first calls of the night, in less competitive states like Kentucky.

19:30 EST (23:30 GMT) – Polls close in three states, including North Carolina, where Harris hopes to end a streak of defeats for Democratic presidential candidates since 2008.

20:00 EST (00:00 GMT) – Polling stations close in Pennsylvania, in 15 other states and in the District of Columbia, as well as partially in Michigan and in four other states.

21:00 EST (01:00 GMT) – All remaining polling locations will close in Michigan. Voting also ends in Arizona, Wisconsin and 12 other states.

22:00 EST (02:00 GMT) – Polling stations will close in Nevada and two other states, and partially in two others.

Typically, votes cast on Election Day are counted first, followed by early and absentee ballots, those that were challenged, and then overseas and military votes.

Local election officials – sometimes appointed, sometimes elected – verify, process and count individual votes, in a process known as a recount.

Ballot verification involves comparing the number of ballots cast with the number of active voters, removing, unfolding and examining each ballot for tears, stains or other damage, and to document and investigate possible inconsistencies.

Counting ballots consists of introducing each of them into electronic scanners which compile the results. Some circumstances require manual counting or double checking of results.

Each state and locality has rigorous rules that specify who can participate in the counting, the order in which votes are processed and which portions are open to the public, including how partisan observers can monitor and intervene in the counting.

The tight margins will force media outlets to wait longer before making their projections, but they also raise the specter of recounts and legal challenges.

In Pennsylvania, for example, a statewide automatic recount goes into effect if there is a difference of half a percentage point between the votes cast for the winner and loser. In 2020, the margin was just over 1.1 percentage points.

More than 100 pre-election lawsuits have already been filed across the country, including challenging voter eligibility and Republican management of voter rolls. The ongoing court decisions in these cases have shaped the race from day to day.

Other scenarios that could lead to delays include election-related unrest, particularly at polling places, and obstacles to counting, such as a broken water pipe at a ballot processing site in Georgia in 2020.

Once all valid votes have been included in the final results and processes such as recounts have been completed, election results are certified, first in local jurisdictions and then at the state level .

A state's executive branch, usually the governor, then certifies what is called a slate of electors who will represent their state in the Electoral College. These electors meet in their respective states on December 17 to vote and send their list to Washington.

On January 6, a new American Congress meets in a joint session to count the votes of the electors, under the presidency of the vice-president in office.

After the 2020 election, Donald Trump refused to acknowledge his defeat and rallied his supporters to march on the Capitol as Congress met to certify Joe Biden's victory.

He urged his vice president, Mike Pence, to reject the results, but Pence refused.

Even after the riot ended and members of Congress regrouped, 147 Republicans voted unsuccessfully to overturn Mr. Trump's defeat.

Election reforms have since made it more difficult for lawmakers to object to certified results sent to them by individual states, and have also clarified that the vice president does not have the power to unilaterally reject votes of the major voters.

Still, election observers expect efforts to delay certification of the 2024 vote to be made at the local and state level.

Mr. Trump, his running mate JD Vance and top Republican leaders on Capitol Hill have repeatedly refused to state unequivocally that they would accept the results of the election if he loses.

The president-elect will be inaugurated on Monday, January 20, 2025 in the Capitol grounds.

This will be the 60th presidential inauguration in United States history.

The new president will take an oath to respect the Constitution and will then deliver his inauguration speech.