Electoral college explained: how Biden faces an uphill battle in the US election

Trump won the presidency in 2016 despite Clinton receiving almost 3m more votes, all because of the electoral college. How does the system work?

When Americans cast their ballots for the US president, they are actually voting for a representative of that candidate’s party known as an elector. There are 538 electors who then vote for the president on behalf of the people in their state.

Each state is assigned a certain number of these electoral votes, based on the number of congressional districts they have, plus two additional votes...