Here's how Hillary Clinton could still win the popular vote... even though she lost the presidential election

Updated: 

Donald Trump may have won the presidential election in one of the most astonishing upsets in US political history, but Hillary Clinton could still receive more votes.

The result would be an ironic twist in an election in which her opponent repeatedly said the system was rigged against him.

Here's what the Republican businessman tweeted just two days before Election Day:

As it turns out, without the Electoral College, President-elect Trump probably would not be heading for the White House - something that Clinton's supporters are questioning at the moment:

A day after Election Day, Clinton held a narrow lead in the popular vote, according to unofficial results.

With nearly 125 million votes counted, Clinton had 47.7% of the vote and President-elect Trump had 47.5%. That is a lead of about 236,000 votes.

So how would Clinton win popular vote?

U.S Democratic Presidential candidate Hillary Clinton
(Reiri Kurihara/AP)

Many states count votes after Election Day, so Clinton is not guaranteed to keep her lead.

However, most of the outstanding votes appear to be in Democratic-leaning states, making it very likely she will become the second Democratic candidate for president this century to win the popular vote but lose the presidency.

The biggest chunk of uncounted votes is in California. Washington State, New York, Oregon and Maryland also have large numbers of uncounted votes. Clinton won all those states, and if the trends continue, she will pad her lead by more than one million votes.

There are also votes to be counted in Arizona and Alaska, two Republican-leaning states. But they are far outnumbered by uncounted votes in Democratic states.

How does the US election system work?

Donald Trump at a rally in Michigan (Paul Sancya/AP)
(Paul Sancya/AP)

Under the Electoral College system, each state gets one vote for each member of Congress representing the state. California has the most, with 55. Seven states have only three.

The District of Columbia has three, even though the nation's capital has no vote in Congress.

It takes 270 Electoral College votes to win the presidency. President-elect Trump's total stands at 279, with races in Michigan, New Hampshire and Arizona too close to call.

Doesn't anyone want to change this system?

Pooling station.
(Victor Calzada/AP)

There have been occasional calls to scrap the Electoral College, with no success. The latest push came after the 2000 presidential election, in which Democrat Al Gore lost to Republican George W Bush, despite winning the popular vote.

Any calls to scrap the Electoral College are not likely to go anywhere this time, either, with Republicans controlling both the House and Senate.

Sen Tim Kaine, the Democratic candidate for vice president, praised Clinton on Wednesday for winning the popular vote.

But when Clinton made her concession speech, she did not mention it.