Donald Trump's victory through the Electoral College has led to renewed scrutiny of the system and calls for the popular vote to be adopted.

Hillary Clinton won the popular vote - despite losing via Electoral College votes – and many see the popular vote as a potentially fairer system.

The Electoral College system sees people vote for electors who in turn vote for the president - rather than a direct popular vote.

The system is enshrined in the US Constitution, making it very difficult to change.

But since November’s election, The National Popular Vote compact has been gaining more attention.

This pact is a legal agreement among some states that they will run elections according to the popular vote, rather than the traditional Electoral College system. It would not contravene the Constitution.

It has already been adopted into law by ten states and the District of Colombia. California, Hawaii, Illinois, Maryland, Massachusetts, New Jersey, New York, Rhode Island, Vermont and Washington states have all signed the legislation.

The states collectively hold 165 Electoral College votes and are traditionally Democrat.

In pictures: US Elections 2016 Show all 15 1 /15 In pictures: US Elections 2016 In pictures: US Elections 2016 Democratic U.S. presidential candidate Bernie Sanders speaks to supporters after rival candidate Hillary Clinton was projected as the winner in the Nevada Democratic caucuses Reuters In pictures: US Elections 2016 Democratic presidential candidate Hillary Clinton takes photos with workers at her campaign office in Des Moines, Iowa AP In pictures: US Elections 2016 Republican presidential candidate Mike Huckabee, second from left, prays before lunch with supporters at Drake Diner in Des Moines, Iowa Reuters In pictures: US Elections 2016 Democratic presidential candidate and former Maryland Governor. Martin O'Malley, speaks during a campaign stop in Waterloo, Iowa AP In pictures: US Elections 2016 Democratic presidential candidate Bernie Sanders speaks, as his wife Jane O’Meara Sanders looks on, at a campaign event at Iowa State University Getty In pictures: US Elections 2016 Republican presidential candidate Marco Rubio speaks at St. Ambrose University in Davenport, Iowa Reuters In pictures: US Elections 2016 Republican presidential candidate Ben Carson speaks at a campaign event at Fireside Pub and Steak House in Manchester, Iowa. Getty In pictures: US Elections 2016 Republican presidential candidate Rick Santorum visiting supporters at a house party in West Des Moines, Iowa Reuters In pictures: US Elections 2016 Republican presidential candidate Donald Trump at a campaign event in Cedar Rapids, Iowa AP In pictures: US Elections 2016 Republican candidate Ted Cruz campaigns at Greene County Community Centre in Jefferson, Iowa AP In pictures: US Elections 2016 Senator Rand Paul speaks during a Caucus rally at his Des Moines headquarters in Iowa Getty In pictures: US Elections 2016 Republican candidate Jeb Bush speaks at a campaign event in Des Moines, Iowa AFP In pictures: US Elections 2016 Former Alaska Governor Sarah Palin introducing the arrival of Donald Trump during a campaign rally in Cedar Rapids, Iowa Reuters In pictures: US Elections 2016 A portrait of Democratic candidate Bernie Sanders at his campaign headquarters in Des Moines, Iowa Getty In pictures: US Elections 2016 Campaign badges on sale ahead of a Trump rally at the Ramada Waterloo Hotel and Convention Centre in Waterloo, Iowa Getty

However, the National Popular Vote compact needs at least 270 Electoral College votes – the same number which guarantees an presidential win – to potentially come into effect.

Advocates of the compact claim it would make people in state with a smaller number of Electoral College votes - such as Hawaii, which only has four votes - feel like their ballot is more worthwhile. This ‘winner-take-all’ system means an individual’s vote makes no difference once the number of Electoral College votes has been secured in their state.

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This means that the concerns of some voters can easily be ignored if their state is regarded as ‘safe’ by a political candidate. It also leads to disproportionate attention being placed on a small number of states during campaigning.

However, political observers say the chances of the popular vote pact being adopted nationally are slim, as it would need some support from traditional Republican states. But the Republican Party has often benefited from the Electoral College system.