Hillary Clinton and Donald Trump have been criss-crossing America in a final push for votes before election day.
Both have been holding rallies in the battleground states of North Carolina, Pennsylvania and Michigan.
Mrs Clinton urged voters to back a “hopeful, inclusive, big-hearted America” while Mr Trump told supporters they had a “magnificent chance to beat the corrupt system”.
Polls give Democrat Mrs Clinton a four-point lead over Republican Mr Trump.
A record number of Americans – more than 46m – have voted early by post or at polling stations.
There are signs of a high turnout among Hispanic voters, which is believed to favour Mrs Clinton.
It was after midnight when the rivals held the final rallies of their campaigns – Mr Trump in Grand Rapids, Michigan, and Mrs Clinton in Raleigh, North Carolina.
“Today the American working class is going to strike back, finally,”
said Mr Trump, pledging to reverse job losses.
Mrs Clinton told her audience that they did not
“have to accept a dark and divisive vision of America”.
It follows a bitter campaign during which the candidates have traded insults and become mired in a series of scandals.