SINGAPORE - As the dust settles following the 2020 US presidential election with democratic candidate Joe Biden ousting President Donald Trump from the White House, we take a look at some of the reasons that caused the incumbent to lose the race and led to Mr Biden becoming America's 46th president.

Why Mr Biden won and Mr Trump lost

1. Covid-19

The coronavirus pandemic and the subsequent economic fall out played a central role in Mr Biden's campaign, allowing him to highlight the incumbent's missteps.

With record surges of Covid-19 infections in the weeks leading up to the election, and with the President catching the virus himself, the Trump administration was seen to have botched handling the crisis.

In the US, Covid-19 has already claimed more than 230,000 lives and the number of new cases continues to rise, with the past few days seeing more than 100,000 new infections daily.

The pandemic has weighed on Mr Trump's approval ratings, which according to a Gallup poll, dipped to 38 per cent at one point in June - something the Biden campaign exploited.

From the President's repeated downplaying of the deadly virus to unsubstantiated claims that Covid-19 was "going to disappear... like a miracle", confidence in the incumbent took a hit, with another poll by Pew Research in October showing that Mr Biden held a 17 per cent point lead over Mr Trump when it came to confidence about their handling of the Covid-19 outbreak.

Mr Biden, on the other hand, laid out his approach to address the disease based on "bedrock science" since the start of his campaign.

He presented to voters detailed plans to combat the virus, including nationalising mask wearing, ramping up on Covid-19 testing and introducing proposals for health care and economic recovery.

2. Less-is-more campaigning

Mr Trump's presidency has been marked by his often controversial and sensationalist statements, some of which were made during his breakneck-paced presidential campaign that saw him criss-crossing the country in recent weeks.

At one point, Mr Trump visited three states in a single day - holding rallies in Michigan, Wisconsin and Las Vegas.

In contrast, Mr Biden adopted a less frenzied campaigning schedule. In recent months, he did the unprecedented, taking entire days off from rallies and events, which drew some criticism.

One thing to note is that Mr Biden is not without slip-ups over the course of his nearly 50 years in public office. And scaling back on his campaign schedule could have been an attempt to limit his verbal stumbles and gaffes, reported Vanity Fair.

Some of his missteps include mixing up living former British prime minister Theresa May with deceased former British prime minister Margaret Thatcher, and saying that "poor kids" were as smart as "white kids" in a 2019 speech - a slip-up that some read as revealing of antiquated views on race and class.

3. Anyone but Trump

The election also became something of a referendum on Mr Trump.

Mr Biden's winning message was simply that he was "not Trump", wrote BBC's North American reporter Anthony Zurcher.

"Biden bet his political fortunes on the contention that Trump was too polarising and too inflammatory, and what the American people wanted was calmer, steadier leadership," he wrote.

"After four exhausting years, many voters simply wanted a presidency they could have on in the background - an occupant of the White House who would behave in a more conventional manner. They had tired of the infantile name-calling, the ugly language and the ceaseless confrontation. They wanted a return to some kind of normalcy," added BBC's New York correspondent Nick Bryant.

Mr Bryant said Mr Trump won the presidency in 2016 partly because he was a "norm-busting political outsider" who was prepared to say what had previously been "unsayable", but this is also the same reason he lost the race in 2020.

Meanwhile, CNN's senior political commentator David Axelrod said Mr Trump's antics over the course of his presidency have not only inflamed his own base but inspired a massive coalition of Americans who are "determined to end his stormy, divisive rule".

He wrote: "Joe Biden pitched himself from the start as the antidote to Trump's hard-edged politics - a healer, not a divider."

4. Stay in the centre

In the lead-up to becoming the Democratic candidate, Mr Biden stuck with a centrist strategy, refusing to back universal government-run healthcare, free college education, or a wealth tax.

His game plan was to hug the middle and propose incremental changes to various policies, while at the same time staying clear of the most far-reaching progressive demands.

"This allowed him to maximise his appeal to moderates and disaffected Republicans during the general election campaign," wrote BBC's Mr Zurcher.

This strategy was reflected in Mr Biden's choice of running mate. He chose Ms Kamala Harris when he could have opted for someone with more support from the Democratic party's left wing.

Ms Harris, who is now Vice-President elect, had in the past rebuffed some demands of the party's rising progressive wing and this might have helped appeal to moderate swing voters in states like Michigan and Wisconsin.

But Mr Biden did move closer to the left on the environment and climate change, perhaps calculating that the benefits of appealing to younger voters for whom the issue is a priority outweighed the risk of alienating voters in energy-dependent, swing-state industries, wrote Mr Zurcher.

5. More money, fewer problems

The Biden campaign had the financial advantage over Mr Trump's in the final weeks leading up to polling day, raising a record US$493.8 million (S$665.9 million) in the two months before the Nov 3 election.

Armed with a total haul of US$761.2 million in 2020, the campaign went on a spending spree buying up television, radio and digital advertising in an attempt to milk the advantage over the Trump campaign that was on a cash crunch during the final stretch.

While the Trump campaign and its shared committees with the Republican National Committee managed to raise US$1.5 billion since 2019, Mr Trump burnt through much of that money in the early stages of the race when voters were not paying much attention, reported the Financial Times.

Mr Trump's campaign began October with just US$63.1 million cash in hand left, an almost 50 per cent drop from the US$121.1 million it had going into September.

Mr Biden's campaign had almost three times as much - US$177.3 million - having ended August with US$180.7 million in the bank.

While a sizeable financial lead is not the sole reason for the win, it gave the Biden campaign an advantage in reaching out to voters and pushing his message until the very end.

The impact of such outreach was amplified due to social distancing and lockdown measures as more Americans stayed at home and consumed more media on various platforms.

For live updates and results, follow our US election live coverage.