Democrat nominee Hillary Clinton today cast her vote along with her husband and former US President at a polling station in Chappaqua, New York.
Clinton gave a thumps-up gesture to the crowd, who swarmed around the couple taking photographs.
After casting her vote, Hillary said, "It's the most humbling feeling. So many people are counting on me. I hope to do the best I can."
Real Clear Politics average of polls gives the lead to Hillary (45.5) over Republican presidential nominee Donald Trump ( 42.2)
The first ballots in the U.S. Presidential polls were cast today, just after midnight, in Dixville Notch, a sleepy hamlet, in New Hampshire, traditionally the first in the nation to vote on Election Day.
The voters also cast ballots early today in two other small New Hampshire communities, Hart's Location and Millsfield.
Unlike in India, every US state counts and declares its result once the polling is over.
A top American pollster has said Hillary Clinton has a 70 per cent chance of winning the White House race against her rival Donald Trump.
FiveThirtyEight website's Nate Silver, who accurately predicted the outcome of 2008 and 2012 presidential elections, said Clinton's projected margin of victory in the popular vote has increased to 3.5 per cent from 2.9 per cent.