US election 2024: What is the Electoral College and how does it work?

Kamala Harris and Donald Trump are hoping to win 270 Electoral College votes to claim victory in this year's Presidential Election with the result likely coming down to the wire

Kamala Harris and Donald Trump are running the the tightest race for the White House in decades with the Electoral College holding the deciding factor in the outcome.

Millions of Americans have cast their ballot today, but their votes will not alone determine the winner with the process going on a state-by-state basis. Both Ms Harris and Mr Trump need to secure 270 Electoral College votes to win the election, rather than a simple majority known as the popular vote - widely predicted to be won by the Democrats this cycle.

To outsiders the process can appear somewhat byzantine and unclear, but there is a method to the apparent madness. The Electoral College consists of 538 electors with each state being awarded a numerical value based on the number of members it has in the House of Representatives and Senate.

For example, the most populous state California has 54 votes in the Electoral College based on its large number of Representatives due to its population and two Senators which each state has. In contrast Wyoming only has three Electoral College votes due to having just one Representative and two Senators.

In 48 states, the winner gets all the electoral votes for that state. Main and Nebraska are somewhat different, assigning their electors via a proportional system - meaning not all necessarily go to the same candidate. When deciding the election winner, the candidate with 270 Electoral College votes will win the race to the White House due to holding a simple majority.

While the election is generally decided in November, there is an Electoral College meeting in mid-December when the electors meet in their states. According to the Constitution, electors do not have to vote for the candidate chosen as their state's winner - although some states mandate it.

But those who do vote for someone else could be fined, disqualified and replaced by a substitute elector. They could even face prosecution by their state.

The confusing nature of the Electoral College has attracted criticism and praise with detractors believing it is undemocratic while advocates say it forces candidates to appeal to a wider range of constituencies.

Dr Thomas Gift, the founding director of the Centre on US Politics at University College London, told The Mirror: "The Electoral College has both pluses and minuses. The downside, of course, is that who occupies the White House doesn’t necessarily accord with the simple principle of majority rule.

"Consequently, critics of the system say that it’s inherently undemocratic. It also concentrates almost all the power into a handful of swing states that aren’t representative of America’s demographics as a whole. The upside of the Electoral College is that it forces candidates to appeal to diverse constituencies, including in rural areas, that they might otherwise write off as unimportant because of their sparse populations. Because swing states don’t lean clearly Democratic or Republican, it also forces candidates to moderate their positions to appeal to the political centre."