Many of the capital's bars in the West End are packed tonight with thousands of people, many of them Americans, gathering to watch the US presidential election results unfold.
Polls that will reveal the probable ratios of Electoral College results that determine the identity of the next US president are expected at around 2am on Wednesday morning. The final result, however, is not expected until around 8am, and many London parties and events will continue right throughout the night until the victor is announced.
In Leicester Square, Yates Wine Lodge is packed with hundreds of election partygoers who have shelled out between £35 and £100 for tickets, with the more expensive tickets including 'all you can eat and drink'.
Parties with big screens are also being held at Planet Hollywood in Coventry St, the Chicago Rib Shack in Knightsbridge, The American Bar in St James' Place and The East Room in Shoreditch.
Dozens of US polls are predicting a significant Obama victory - and not one poll is predicting a win for Republican John McCain. The expected record turnout is bound to be good news for Barack Obama as the majority of the extra voters will most likely be voting Democrat.
If Obama does win, his supporters will be laying on a massive victory party in Chicago, with over a million revellers expected to celebrate.