How will the BBC report the results of the US election? This guide explains where the results come from, what exit polls are, and how states are called.
What is the source for the BBC's election results?
This year the BBC is reporting state calls made by the ABC network.
When a state call is made by ABC, our results desk in Washington will update the electoral college vote tally for each candidate.
All other election data, including popular votes and Congressional results, is provided by the Associated Press (AP).
How do the results take shape and what are "projected results"?
Initially the outcome of the US election is likely to be a "projection", based on exit polls and/or partial results. This means the result will be labelled as projected until all the votes are counted.
The reason for this is that states are often called, or declared, for a candidate, on the basis of incomplete figures. The American electoral system enables each state to release partial results to the public well before they have counted every single vote. Results are later confirmed once all the votes have come in.
For races that are not very close ABC, along with other US networks, are likely to project a winner as soon as the polls close, based on exit poll data. For closer races the networks will wait until there's more actual vote data. It can take hours or even all night.
Are the projections ever wrong?
Yes, particularly if the election is very close.
What is an exit poll?
Exit polls are gathered by speaking to members of the public after they have voted.
This year exit polls are being handled solely by Edison Media Research and Mitofsky International.
The BBC does not have access to the detailed exit poll data.
Is Washington DC a state?
No. DC, or the District of Columbia, is not a state, but it does receive three electoral college votes. DC is able to vote for president but it does not have senators or congressmen of its own.