TORONTO -- The fate of the U.S. presidential election has boiled down to four states where ballots continue to be tabulated.

By Saturday morning, Democratic candidate Joe Biden was six electoral college votes shy of winning the presidency, according to The Associated Press’ tracking. U.S. President Donald Trump had a steeper hill to climb to reach the 270 electoral college votes required to win as he was still 56 votes away.

Biden only needs to win one of the four battleground states that haven’t been called yet – Georgia, Pennsylvania, North Carolina, or Nevada – to reach 270. Trump, on the other hand, must take all four states to beat Biden. Trump is currently trailing in three of the four races.

While the remaining ballots are being counted, here’s a look at the four battleground states still in play.

Click here for our live map with up-to-date results.

GEORGIA

RESULTS: Too soon to call

WHO WON IN 2016: Donald Trump, by 5.1 points

ELECTORAL COLLEGE VOTES: 16

Despite Trump’s early lead in the state after the in-person votes were counted, Biden gained ground as more mail-in ballots were tallied. So much so that by Saturday morning, the Democratic candidate had eked out a lead of more than 7,200 votes over Trump.

That doesn’t mean that Biden has won Georgia, however, as the state’s overseas, military and provisional ballots were left to be counted. On top of that, the state is headed to a recount, officials confirmed.

The Republicans have carried Georgia in every election dating back to 1992, when former Democratic president Bill Clinton won. In 2016, Trump handily won the state.

PENNSYLVANIA

RESULTS: Too soon to call

WHO WON IN 2016: Donald Trump, by 0.7 points

ELECTORAL COLLEGE VOTES: 20

The contest for Pennsylvania and its coveted 20 electoral college votes has been incredibly close as well as important this election. As of Saturday morning, Biden jumped ahead of Trump in the critical Midwest state with a lead of more than 28,000 votes, a lead that Biden’s campaign predicted days ago.

Trump started out strong in the industrial state he took from the Democrats in the 2016 election, but as more mail-in ballots were tallied and results trickled in from Philadelphia and Pittsburgh, Biden has caught up.

The late surge for Biden was expected because mail-in ballots in Pennsylvania could only be opened on election day or later, and Democrats tend to vote by mail at a higher rate than Republicans.

It’s mathematically impossible for Trump to win the presidency without Pennsylvania. His campaign has already launched a lawsuit in hopes of challenging the results despite a lack of evidence of large-scale wrongdoing.

On election day, Biden spent the morning in his childhood hometown of Scranton, Penn. trying to reinforce his image as “Middle Class Joe” in the blue-collar state.

NEVADA

RESULTS: Too soon to call

WHO WON IN 2016: Hillary Clinton, by 2.4 points

ELECTORAL COLLEGE VOTES: 6

With only an estimated 87 per cent of the expected vote tallied, it’s still too early to declare a winner in Nevada.

As of Saturday morning, Biden led the state by more than 22,600 votes, but there are still many ballots left to be counted in the coming days. Under state law, the ballots will still be accepted as long as they were postmarked by Nov. 3.

In the 2016 election, Democratic candidate Hillary Clinton narrowly beat out Trump in Nevada and the state has been blue-leaning over the past decade. The last time a Republican contender took the state was in 2004 when George W. Bush won.

NORTH CAROLINA

RESULTS: Too soon to call

WHO WON IN 2016: Donald Trump, by 3.6 points

ELECTORAL COLLEGE VOTES: 15

As of Saturday morning, Trump maintained a lead over Biden in North Carolina. The president was ahead by more than 76,400 votes with an estimated 99 per cent of the expected vote counted.

Election officials say they have more outstanding mail-in ballots and potentially thousands more provisional ballots to count before the final results will be known. They said they won’t have the final results of the mail-in ballots until Nov. 12 or Nov. 13.

Trump won this medium-sized battleground state by a comfortable margin in 2016.

ARIZONA

Joe Biden wins Arizona

RESULTS: Biden wins, according to Associated Press

WHO WON IN 2016: Donald Trump, by 3.5 points

ELECTORAL COLLEGE VOTES: 11

Biden has won Arizona, the Associated Press declared at 2:50 a.m. Wednesday. Most other major news networks have not followed suit as they await more results.

The AP said Thursday it is still monitoring the vote count in the state.

“The Associated Press continues to watch and analyze vote count results from Arizona as they come in,” said Sally Buzbee, AP’s executive editor. “We will follow the facts in all cases.”

Trump’s campaign has said it’s confident the president will overtake Biden once all votes are counted.

Arizona hasn’t voted for a Democrat since Bill Clinton’s victory in 1996. But the state has continued to shift more to the left in recent years.

Some pundits viewed Arizona as part of Biden’s “plan B” approach to win the White House if he failed to clinch Pennsylvania.

With files from The Associated Press