The United States voters do not technically elect their president. Instead, the results of the general election merely provide a guide for Electoral College members. They, in turn, pick the President.
The popular vote not always decides the winning candidate. In the 2000 election Democrat Al Gore received more of the popular vote, but Republican George W Bush got the Electoral College’s nod after the US Supreme Court shut down the Florida recount.
There are 538 popularly-elected members of the Electoral College, allotted to each of the 50 states and the District of Columbia based on their representation in the US Congress. The smallest states have three members while the largest state, California, has 55.
This ends up giving smaller states much more power as the proportion of members does not equal the proportion of population. Washington DC, which has no representation in Congress, has three members, the same as the smallest states.
It takes 270 electoral votes to win election. The electors are pledged to one candidate or the other but there is no federal law requiring them to vote that way.
There have been several incidents in which an elector has voted for someone other than the major candidates. However, in 2000, the Florida electors stuck by the decision of the US Supreme Court even though they had the power to give Al Gore the victory.
In 48 states and the district, the candidate who wins the popular vote wins all of the state’s electors. Two US states Nebraska and Maine have a proportional system of awarding electors.
Electors, who are picked by the respective political parties, make two selections – for president and for vice president.
Because a candidate could run up a big vote count in some states but lose others by narrow margins, the winner of the popular vote might not have the most electoral votes.
The Electoral College has three times picked the candidate who lost the popular vote: Republicans Rutherford B Hayes in 1876, Benjamin Harrison in 1888 and George W Bush in 2000.
This unique electoral system was the result of a compromise by the writers of the US Constitution in the 18th century between those who wanted direct popular election and those who wanted state legislatures to decide.
The real battle is for the “swing states” where the outcome is uncertain including Arizona, Colorado, Florida, Iowa, Michigan, Nevada, New Hampshire, North Carolina, Ohio, Pennsylvania, Virginia, and Wisconsin.
Together these states have 157 electoral votes up for grabs. Whoever can carry enough of those states to bring the overall electoral vote total to the magic figure of 270, will win.
The biggest Electoral College prizes are California with 55 votes, Texas with 38, and New York and Florida, each having 29 electoral votes.
In what is largely a formality long after the winner has been determined, each state’s electors will meet on the Monday 19 December in their home states and cast their votes for president and vice president.
Congress will meet on 6 January to conduct an official tally.
The President-elect will take the Oath of Office and becomes the 45th President of the United States on 20 January 2017.