How is the most unpopular and divisive president on his way to a second term?

Long after nightfall, an exultant Donald Trump takes the stage in a hotel ballroom, punching the air in front of giant TV screens. A delirious crowd is wearing “Keep America Great” caps and chanting “USA! USA!” These are the early hours of 4 November 2020 and lightning has just struck twice: Trump has won a second term.

For millions of people outside America, the notion of Trump’s re-election might seem hard to believe. How could one of the most unpopular and divisive presidents in the country’s history, impeached for high crimes and misdemeanors and reeling from one self-inflicted crisis to another, possibly win the White House again?

Yet many here in the US have a gut feeling that is precisely what will happen.

“The world looks at us and says, ‘How can the United States re-elect this guy?’” said Wendy Schiller, a political science professor at Brown University in Providence, Rhode Island. “But when you’re the average voter and you’ve been through six to eight years of recession and then you’ve finally got a good economy, that’s a difficult barrier for Democrats to break through.”

Related: 'I'd like to vote Democratic': the swing voters who want a reason not to back Trump again

Indeed, Trump has several powerful factors in his favor.

Voters tend to stick with what they know: no incumbent has lost the White House since George H W Bush’s defeat at the hands of Bill Clinton in 1992. That was during a recession and tax increase, whereas Trump is enjoying steady growth, stock market records and the lowest unemployment for half a century. Some 56% of Americans approve of Trump’s handling of the economy, his strongest rating on the issue since entering office, according to a Washington Post-ABC News poll this week.

He also has advantages of time and money. Trump registered with the Federal Election Commission on the day of his inauguration. He has, in effect, been campaigning ever since with a potentially lethal combination: on the one hand, rollicking rallies and tweets that sell a crude populist message; on the other, a clinically rigorous data-gathering and voter mobilisation operation that leaves nothing to chance. Whereas his first campaign was like a plane being built in midflight, the 2020 version has the power and prestige of Air Force One.

Trump, 73, might even suffer another heavy defeat in the popular vote, while winning the handful of key states that decide the electoral college. Schiller added: “The key question in 2020 is: will there be any drop off from the very narrow coalition that elected him?

“First, that would be caused by Trump fatigue, a drop off of voters who say, ‘I’m going to sit this one out’. That would hurt him in states like Minnesota, which he lost last time, and North Carolina, which he won.

“The second cause would be any dip in the economy, which has been Trump’s coat of armor, his shield, and makes him impenetrable. In a good economy, I don’t think there’s an appetite for radical change.”

But Trump’s fate might also rest on something beyond his control: his opponent.

Democrats are about to begin voting in what has the makings of a messy and complicated primary. The president’s two most effective nemeses – House Speaker Nancy Pelosi and intelligence committee chairman Adam Schiff – are not on the ballot. Whoever does prevail may not be able to unite or enthuse a divided party.

Whereas Trump’s 2016 effort against Hillary Clinton was insurgent, shambolic and run on a shoestring, this time he has the full weight of the Republican party behind him. The Trump campaign, Republican National Committee (RNC) and related joint committees together raised a staggering $463m in 2019 – over $200m more than Barack Obama in 2011. They have nearly $200m cash on hand heading into the election.

Furthermore, Trump’s re-election campaign and the RNC already have almost 400 staff across 18 target states. The campaign has announced “Trump victory leadership teams” for 49 states and five territories so far. Its manager, Brad Parscale, is orchestrating a sophisticated data operation that harvests the details of every supporter who donates, buys merchandise, enters a competition or attends a rally.

Many experts say the Trump campaign outplayed Democrats on Facebook in 2016 and is determined to do so again with targeted advertising. Facebook has, controversially, announced that it will not fact check political ads on its platform.

The president’s campaign ads so far are simplistic yet brutally effective. They portray him as a no-nonsense commander in chief – building a border wall, appointing supreme court justices, cutting taxes and taking out terrorists – while rubbishing Obama and accusing Democrats of indulging in political theatre such as impeachment. A $10m ad will be shown during American football’s showpiece Super Bowl game next Sunday.

But Trump also hopes to win through force of personality. He has held 10 rallies in the past three months. Rally warm-up acts include the president’s son, Donald Trump Jr, who has become adept at channeling his liberal-baiting message. A combination of incumbency and outrageous behavior will ensure continued media coverage.

His pitch is us versus them. Strategically, that means Trump is likely to focus on energizing his base in critical states such as Florida, Michigan, Pennsylvania and Wisconsin, in part by vilifying his opponent and relying on Republican efforts to purge voter registration rolls.

The rout of Republicans in the 2018 midterms, however, suggests that the outcome is far from certain.

Michael Bloomberg, the billionaire businessman who poured a fortune into those races, has pledged to fund 500 staffers in battleground states until election day even if he loses the Democratic nomination. And even if Trump is acquitted by the Republican-controlled Senate, the stench of impeachment will cling to him in November.

Much will depend on Democrats’ choice of nominee. In rally speeches and tweets, Trump has made little secret of his line of attack. Former vice president Joe Biden would, like Clinton in 2016, be framed as offering a third term of Obama and as a creature of the Washington swamp with misleading claims of corruption against his son, Hunter, over his business dealings in Ukraine.

Senators Bernie Sanders and Elizabeth Warren, meanwhile, will be painted as radical leftists who put Americans’ prosperity at risk. Trump now has a well rehearsed stump speech that riffs on the perils of socialism in Venezuela before veering off into the Green New Deal and the bird-slaying potential of wind farms.

John Zogby, a pollster, author and strategist, said: “He might very well be re-elected. The nation’s split, and what compounds things for those who want to defeat him is that those who want to defeat him are split. And if anyone knows how to take advantage of a wedge and drive that wedge further, it’s the incumbent and his capacity to use social media.”

Charlie Sykes, a conservative author and broadcaster and Trump critic, agrees. “His chances may be actually stronger than 50-50,” he said. “Part of it is the nature of the electoral college and his success in tribalising the electorate and creating alternative reality silos. But also I’m not convinced the Democrats have got their act together.”

Sykes, who hails from the pivotal state of Wisconsin, believes that Biden has the best shot but remains a flawed candidate. “The Democrats don’t have a Barack Obama. They don’t have a charismatic leader who’s going to inspire people. I do think that Bernie Sanders would have a Jeremy Corbyn-like problem: swing voters are not as into revolution as some Democrats believe.”

If there is lesson from 2016, when a reality TV celebrity with no political experience came from nowhere to win the White House, it is that anything can happen. Trump’s equivocation over white nationalists marching in Charlottesville, caging of children on the Mexican border, coercion of Ukraine for personal political gain and 16,241 false or misleading claims over three years (according to a Washington Post count) are apparently no longer disqualifying for millions of voters.

Moe Vela, an LGBTQ and Latino activist and former senior adviser to Biden, said: “We should figure out who they are and why they broke in his favor last time. We’ve got to better understand what compels a decent person to continue to support something so violent to what used to be our traditional American values.”

He added: “If we continued to talk past or around those people or distance them or alienate them, then his chances of reelection are strong. Understand their angst. Understand their plight. How could a decent person be OK with 15,000 lies? That’s the riddle right there. What would cause them to abandon the values they were raised with to support a man who paid a porn star he had sex with?”

In September 2002, George W Bush, an unpopular Republican president, offered some characteristically mangled syntax: “Fool me once, shame on... shame on you. Fool me.. You can’t get fooled again!” Bush went on to win reelection. Now Trump is attempting to repeat the trick.

Fool me once, shame on you. Fool me twice – shame on me.