Donald Trump’s run of good luck could end this weekend – if Joe Biden does the right thing | Jonathan Freedland

You can see why they think he’s God’s anointed one. You can understand why Republicans cheered when Donald Trump repeatedly claimed the divine as his number one supporter, declaring with certainty that he had God on his side. To the faithful gathered at the Republican national convention in Milwaukee on Thursday night, none of that would have sounded like exaggeration – and not only because their nominee for the US presidency had survived an assassin’s bullet. It’s also because Trump has been on a run of extraordinary good fortune – one that might be just about to end.

Of course, it was that brush with death at a rally in Pennsylvania last weekend that the former and would-be future president had in mind when he spoke of “a providential moment”. The shooting, and Trump’s ability to shrug off injury, raising his fist in bloodied defiance, has prompted his most fervent believers to cast him as a living martyr to their cause. The Republican party had already transformed itself into a cult of personality. But to see delegates wearing bandages on their right ears as a mark of love for, and identification with, their leader is to realise that that cult has become messianic.

Still, even the most godless Republican may have found themselves wondering if Trump does indeed have a friend upstairs. For three straight weeks, everything has gone his way.

Trump’s hot streak began with the TV debate against Joe Biden at the end of June – a debate that, it’s worth remembering, would typically have taken place in the autumn had not the Biden team insisted it must happen sooner. That was a 90-minute disaster for the president who, when he wasn’t struggling to complete sentences, stared vacantly into space, looking every one of his 81 years.

That triggered a panic among Democrats , three long weeks of internal agonising as elders and bigwigs sought to navigate between the pride, and stubbornness, of a president who they believe deserves respect for a consequential term in office, and a party ever-more convinced that he will not only lose the White House, but will take Democratic candidates for the House and Senate down with him. That process may reach its climax this weekend, but not before it has handed Trump a delicious contrast: Democrats divided and distracted, Republicans unified and focused.

Meanwhile, the courts have been smiling on Trump, whether it’s six judges of the supreme court, three of whom were appointed by him, granting presidents near total immunity for their official acts, or a Trump-appointed judge throwing out what most agreed was the strongest of all the legal cases against him, relating to his alleged retention of classified documents.

That’s allowed him to sit back and enjoy the show. He’s watched as, to take one example, Biden gave a decent performance at a post-Nato summit press conference, giving detailed answers on foreign policy – while all anyone remembers is that he introduced Volodymyr Zelenskiy as “President Putin” and referred to Kamala Harris as “Vice-President Trump” .

But it’s the assassination attempt and the TV debate that are the bookend events of these remarkable few weeks, reinforcing what was already Trump’s chosen frame for the campaign: strong v weak. As one senior Democrat put it to me: “The Republicans have a guy who bullets bounce off of. We have a guy who can’t handle a flight of stairs.” The polls are bleakness itself for Democrats, with Trump leading Biden not only in all the key swing states , but even in once solidly Democratic terrain – with Virginia and even, incredibly, New York now deemed “battleground” states. No wonder Republicans were talking this week of a November landslide.

Then, just in case any part of the narrative was insufficiently vivid, while Trump was being hailed as a messiah in Milwaukee, Biden contracted Covid . Now he is isolated, in every possible sense.

Except maybe it’s possible to be too lucky. Trump is so far ahead, his numbers so strong, that Democrats have stepped up their post-debate push to get Biden to withdraw from the race. Privately at first and then, when Biden refused to budge, publicly via well-placed leaks, congressional leaders, big league donors and arguably the party’s sharpest political brain, the former House Speaker Nancy Pelosi, have spelled it out for the president , telling him he cannot win. “It’s over,” one party veteran tells me. “He’ll be gone by Monday.”

If that’s right, then Trump’s lucky streak will surely be at an end. His entire campaign has been predicated on Biden being his opponent. Facing someone else means three fundamentals of the race would be altered. First, media attention will shift away from him to the shiny object of a new Democratic nominee. Second, he, not his opponent, will be the oldest person in the race. And third, Trump should no longer have the “change” message – so potent in this age of anti-incumbency – all to himself.

That last element depends on whom Democrats choose and how they do it. If Biden stands aside and there is a quick coronation of his deputy, Harris, then Trump will cast her as the status quo. There will be a cacophony of racist and misogynist dog whistles, along with a related effort to present her as lacking a democratic mandate and dangerously leftwing .

But there is another way to do it. Even some of Harris’s backers favour a mini-primary, which could amount to a fortnight or so of TV debates before the 4,000 or so Democratic delegates cast their votes. Not enough, to be sure, but that would bestow some democratic legitimacy on the eventual winner and offer at least a glimpse of who flourishes and who wilts under national scrutiny. The ballot itself should happen before the party convention in Chicago on 19 August, so that that gathering can be a showcase rather than a floor fight.

I know – we’re getting ahead of ourselves. But as Democrats head into a fateful weekend, they should know they have little to fear from what may lie ahead. A contest could demonstrate the party’s energy and vigour, its deep bench of new talent, drawing the contrast with the creepy cult it opposes. Given the number of Americans who have been saying for a year or more that they want a choice other than Trump v Biden, there is every chance the election could be upended, with the polls looking radically different almost straight away.

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And Trump showed again on Thursday night how eminently beatable he is. His speechwriters wanted him to adopt a kinder, gentler tone – a man chastened by his brush with death, bent on healing and national unity. He managed it for a while. But soon he was veering away from the teleprompter, with rambling diversions into all the old, dark greatest hits: “crazy” Pelosi, migrants as an “invasion” of killers and criminals, the election that was stolen from him.

The stakes are too high, for the US and the world, to let Democrats cede the 2024 contest to Trump, which is what a continued Biden candidacy would do. The hope is that Biden himself reaches that conclusion in the next day or two, and performs what will be his last great act of public service. Because whatever the Republican faithful may say, this decision is not in the hands of the Almighty – it is in the hands of human beings who, whatever their fears and frailties, need to act and act now.

• Jonathan Freedland is a Guardian columnist