The United States’ Republican president, Donald Trump, has a record of declaring himself a winner and calling his opponents losers. In an unprecedented move, he has done that with the presidential election , saying even before millions of votes have been counted that he has defeated Democratic rival Joe Biden and, alleging fraud, vowed to challenge the result in the Supreme Court. In reality, the outcome is on a knife edge, with both contenders running neck-and-neck in key swing states that could take days or weeks to decide. With the nation deeply divided and tensions so high that there is a risk of unrest, this is a time for calm and cool heads, not populist tricks and power grabs. Trump set the tone for his presidency at his inauguration by bragging of a record-setting turnout even though side-by-side images of previous events showed that to be untrue. After midterm elections in 2018, he messaged on Twitter of a “tremendous success tonight”; his party instead had lost the House of Representatives to the Democrats. But his falsest declaration of victory has been against the Covid-19 pandemic, which is still causing record infections across the US and on the eve of the election, had claimed more than 230,000 lives. Shortly before Trump made his election claim, Biden said he was “on track” to victory. But with a likely record turnout and more than 100 million postal votes cast due to fears about the coronavirus, it is premature for any candidate to credibly declare they have won. Many postal votes have still to be counted and unknown numbers have yet to be received. It is also wrong to allege that fraud has taken place when there is no such evidence. Trump has been a polarising president; he has his avid supporters, but his opponents claim he has damaged institutions and the nation’s international standing. The election campaign was arguably the most spiteful and ill-tempered in American history. Results so far have shown the incumbent has done better than opinion polls had predicted and there is a possibility that he will win a second four-year term. But every legal vote has to be counted before victory can be claimed. All awaiting the result should take a deep breath.