Millions of Americans vote for the next US president
Tens of millions of Americans are voting to decide whether to re-elect Democratic President Barack Obama or hand the job to Republican Mitt Romney.
Polling stations will start closing in eastern states at 18:00 EST (23:00 GMT) and a winner could become clear within hours.
Turnout is crucial, with polls suggesting a neck-and-neck race, but giving the president a slender lead in crucial swing states.
The BBC's Steve Kingstone reports.
For in depth coverage as the US goes to the polls: BBC US election special report