U.S. voters are casting ballots Tuesday to decide who will succeed president George Bush in the White House - Republican John McCain, or Democrat Barack Obama.
Voting is underway in most of the nation's states and in Washington, D.C. Long lines are forming at polling stations across the country, as officials prepare for a record turnout of voters, who are eager to cast ballots in this historic election.
If Obama is elected, he will become the nation's first African-American president. If McCain is chosen, he will become the oldest man elected to a first term, and his running mate Sarah Palin will become the country's first female vice president.
Obama leads McCain by about eight percentage points according to an average of public opinion polls (compiled by realclearpolitics.com), but McCain believes his campaign has enough momentum to win in key states.
McCain is campaigning in Colorado and New Mexico, hoping to gain a last-minute boost to catch up to his rival. Meanwhile, Obama has voted in his home state of Illinois, before campaigning in the historically Republican state of Indiana.
The economy became the central issue in the last few months of an epic presidential campaign.
McCain has pledged to cut wasteful spending and to tackle corruption in Washington, while Obama has pledged tax cuts for the middle class.
Both candidates have promised to bring change to Washington, and have sought to distance themselves from unpopular president George Bush.
Also today, Americans will choose all 435 members of the House of Representatives, who serve for two years, and about one-third of the 100 Senators (35) to serve a six-year term.
In the United States, each state is allotted electoral votes depending on its population and congressional representation. The winning candidate must get at least 270 out of 538 electoral votes.
Some information for this report was provided by AFP, AP and Reuters.