More than four million people have signed a petition calling for the members of the US Electoral College to name Hillary Clinton the next President of the United States instead of Donald Trump.

While this is highly unlikely to succeed, it has highlighted some Americans’ frustration over their idiosyncratic electoral system, which one California senator is trying to abolish with new legislation.

The President is not directly chosen by voters, but by ‘electors’ that people in a state vote for.

Theoretically, the 538 electors set to meet on 19 December could ignore their states’ votes and choose to cast their ballots for Ms Clinton instead of Donald Trump.

The online petition, set up a week ago by Elijah Berg, said they should do just that because “Mr Trump is unfit to serve” as President.

“Hillary won the popular vote. The only reason Trump ‘won’ is because of the electoral college,” wrote Mr Berg.

“But the Electoral College can actually give the White House to either candidate. So why not use this most undemocratic of our institutions to ensure a democratic result?”

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The Electoral College system was established to ensure regional balance — it makes it mathematically impossible for a candidate with large amounts of support in just one region to overwhelm the vote.

The system allowed Donald Trump to win the presidency despite Hillary Clinton's lead of nearly one million votes.

The more people in a state, the more electors an area has. For example, Texas has a population of 25 million and is afforded 38 Electoral College votes, while Delaware has a population of 936,000 and has only three votes.

Mr Trump needed to reach a majority of 270 Electoral College votes before Ms Clinton to be elected. On election night he took 290 of the votes, while Ms Clinton won 232, although one state is yet to be called.

However, Ms Clinton received 61.99 million votes in total, compared to Mr Trump's 60.95 million, according to CNN.

“The Electoral College is an outdated, undemocratic system that does not reflect our modern society, and it needs to change immediately,” said Barbara Boxer, a Democratic Senator in California.

Ms Boxer introduced legislation on Tuesday to rid the United States of the Electoral College system.

“Every American should be guaranteed that their vote counts,“ she said.

However, like the petition, Ms Boxer’s attempt at electoral reform is a long shot. Hundreds of Constitutional amendments have been proposed over the decades concerning the Electoral College, but none has succeeded.

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Amending the Constitution requires the agreement of two-thirds of Congress and ratification by three-quarters of the states.

In 1987, the American Bar Association criticised the Electoral College as “archaic” and “ambiguous”, and polling suggested 69 per cent of lawyers favored abolishing it.

And according to US polling organisation Gallup, over the years Americans have expressed a strong preference for the system to be scrapped.

In a 2013 poll, 63 per cent of Americans said they would vote for a law that would scrap the Electoral College if they could.

Mr Trump himself strongly criticized the system in 2012, calling it a “disaster.”

On Tuesday, however, he changed his tune. “The Electoral College is actually genius in that it brings all states, including the smaller ones, into play. Campaigning is much different!” he tweeted.

In 48 of 50 states, rules require all of a state's electors to cast their votes for whichever candidate wins the popular vote there on a winner-takes-all basis.

“If they all vote the way their states voted, Donald Trump will win. However, they can vote for Hillary Clinton if they choose,” said the petition.

“Even in states where that is not allowed, their vote would still be counted, they would simply pay a small fine – which we can be sure Clinton supporters will be glad to pay.”

Members of the Electoral College who do not vote for their state's chosen candidate are known as 'faithless electors'.

Since the College was founded, there have been 157 faithless electors, according to non-profit political organisation FairVote – but 71 of these were because the original candidate died on the day before the votes were cast.

Laurence Tribe, a Harvard Law School professor, told USA Today the petition was "doomed to fail" as neither Barack Obama nor Hillary Clinton supported it.

“Both incumbent President Obama and the candidate who won a popular majority nationwide, Hillary Clinton, have made such a huge point of accepting Donald Trump as the President-elect," he said.