Joe Biden has taken a commanding 25-point lead in close counties where in 2016 Donald Trump and Hillary Clinton were within 10 points of each other, a poll released Saturday revealed.

The Fox News poll shows Biden ahead with 57 per cent support to Trump’s 32 per cent in close counties – defined by the poll as counties where Hillary Clinton and Trump were within 10 percentage points of each other in 2016.

The former vice president also has a 49-40 per cent lead over Trump in the national head-to-head matchup, according to the first Fox poll taken after Biden became the assumed Democratic candidate.

When looking at swing states overall – which were a considerable factor to Trump winning in 2016 – Biden’s lead shrinks to an eight-point margin.

Joe Biden is shown with a commanding 25-point lead against Donald Trump in key battleground counties. The new Fox News poll has Biden with 57 per cent support in these areas to Trump's 32 per cent

The counties considered in the poll are ones where Donald Trump fell within 10 points of Hillary Clinton in the 2016 elections

Although the primary election has been derailed due to the coronavirus outbreak this month, the last elections held March 17 cemented Biden’s position as the front-runner and presumed nominee after he won all three states participating – Arizona, Florida and Illinois.

Bernie Sanders has still not dropped out of the race yet, even though it’s virtually impossible for him to best Biden at this point as he’s more than 300 delegates behind his establishment competitor.

It is still unclear how the rest of the primary elections will pan out as the nation deals with adapting as several states have gone on lockdown and thousands have been diagnosed with coronavirus.

The timing of this poll, taken March 21-24, is encouraging for Biden considering it was conducted during a time when Trump’s approval rating skyrocketed in the midst of the coronavirus crisis.

This could be a signal that the rally behind Trump during this time might not translate to votes in November.

Biden also has a massive boost in support, according to the poll, due to his pledge to choose a woman as his running mate – 63 per cent of voters approve of his promise.

When hypothetical Democratic tickets were put up against Trump’s ballot with Vice President Mike Pence, Biden still emerged victorious.

The Biden ticket with former Democratic primary candidates and U.S. Senators, Kamala Harris of California and Amy Klobuchar of Minnesota both showed the former vice president winning with 50 per cent support to Trump-Pence’s 42 per cent.

If Biden were to run with Elizabeth Warren, also a former Democratic candidate and a current Massachusetts senator, the win goes up by 2 percentage points to 52 per cent to 42 per cent.

The poll has a margin of error of plus or minus 3 percentage points and was taken among 1,011 registered voters.