Imagine that the polls have closed in Florida, counties are beginning to report early vote counts, and it looks like former Vice President Joe Biden is way ahead. An hour later, Pennsylvania counties begin to report and it seems to be a slam dunk for US President Donald Trump.

Don’t be fooled, voting experts and academics say. Early vote counts in the most competitive, battleground states can be particularly misleading this election because of the surge in mail-in or absentee ballots, and the different ways that they are processed.