As with most recent elections for the US presidency, this year’s battle between Donald Trump and Hillary Clinton will be decided by voters in a dozen or so battleground states.
Under the American voting system, a candidate needs to win a majority of the 538 delegates who will constitute the electoral college that officially anoints the next president in December.
While Mr Trump could win the popular vote in a majority of the 50 American states, opinion polls suggest he will not secure a majority of delegates because Mrs Clinton is poised to win delegate-rich contests in the most populous states like California and Illinois.
One of the candidates will win control of the college when he or she secures at least 270 delegates at this week’s election.
With less than a day to go before the election booths open, opinion polls suggest Mr Trump is certain to win in 18 states that will likely earn him 164 delegates.
Mrs Clinton is in the box seat to carry at least 16 states, plus the District of Columbia that will yield her 216 delegates.
So the battle for the keys to the White House will be decided by a clutch of cliffhanger states that collectively account for 158 delegates.
Here is a summary of the six states most likely to shape the outcome.
Florida (29 delegates)
Along with Ohio, Florida is a consistent bellwether of presidential elections. It sealed Al Gore’s fate in the knife-edge 2000 election won by George W. Bush.
There’s a strong chance that Trump will establish an early lead in the Florida count because returns from Republican strongholds in the northern part of the state are traditionally declared earlier than the Democratic-leaning southern counties.
Obama carried the state in 2008 and 2012 after snaring big margins among Hispanic voters in Miami. Opinion polls put Clinton ahead by an average of 1 per cent, which means the fight for the state’s delegates could go down to the wire again.
Ohio (18 delegates)
Mitt Romney’s chances of winning the presidency were dealt a fatal blow early in the count of the 2012 election when Barack Obama began building a material lead in Ohio.
Every presidential winner since 1964 has carried Ohio, but there could be a break with history this year. Opinion polls indicate that the state is more likely to direct its delegates to Trump.
Media reports suggest that the Democratic Party is finding it difficult to mobilise the African-American vote in the state.
Clinton led every opinion poll on voting intentions in Pennsylvania since late July, but the latest poll conducted in early November indicates that the candidates are at level-pegging.
Pennsylvania is a Democratic-leaning state, having voted against Republican nominees in the last six presidential elections.
The decline of steel-making in the Pittsburgh city region has put the state in play at this election. Republican strategists are hoping that Trump’s promise to impose tariffs on Chinese steel imports will turn blue-collar voters against Clinton.
North Carolina (15 delegates)
Historically, this state is Republican-leaning. After winning in 2008, Obama lost to Romney in 2012 in what was the tightest result of the 50 state contests.
Momentum was with Clinton since the middle of August, but her ratings in the opinion polls nose-dived last week after revelations that the FBI had re-opened its probe into her private emails.
Trump’s average lead in the polls up to November 1 was around 2 per cent.
A high turnout of African-American electors in pre-poll voting augurs well for Clinton. Should be tight.
Colorado (9 delegates)
Trump strategists believe that support for their candidate has surged in Colorado in recent weeks.
However, he has not led a single poll conducted in the state since the middle of September.
Clinton’s average lead in the polls conducted this month is 3 per cent. Reports of high turnouts of Hispanic voters in early voting probably indicate that Trump faces a rocky climb.
Nevada (6 delegates)
Before the FBI helped to turn the momentum of the election Trump’s way in late October, Clinton seemed to be cruising in Nevada. Now that the FBI has cleared her of any wrongdoing, Democrats will be hoping that she can retrieve the 4 per cent margin she enjoyed for most of last month.