With just days left in his duel against Kamala Harris, in what could be one of the closest elections in US history, Donald Trump has made no attempt to appeal to moderates, instead doubling down on his provocations, fiery diatribes and often profane insults.

Some see the strategy as a smart way to appeal to disaffected young men. But others say it may be ineffective, particularly as Trump’s Democratic rival Kamala Harris has gone out of her way to appeal to Republican moderates.

The vice president has been campaigning alongside Liz Cheney, a famously conservative former Republican congresswoman, while promising to be a president “for all Americans.”

Harris has also abandoned several of her former positions — on topics ranging from climate to gun control — to avoid being seen as overly progressive ahead of an election that could be decided by a few thousand votes.

A deliberate strategy

But Trump? Quite the opposite.

As he holds final rallies in a gruelling schedule taking him from central New York to the southern state of Georgia, the Republican has dialed up, not toned down, his rhetoric.

Migrants? They are “terrorists, assassins” who are “poisoning the blood of our country.”

And Harris? He calls her a “stupid” person who should have to pass a cognitive test; or more crudely, “a shit vice president.”

Nor has he spared his vitriol when it comes to the numerous Republicans from his first administration who are now sharply critical, from former vice president Mike Pence to former chief of staff John Kelly, who said Trump fits the definition of “a fascist.”

Trump has even lashed out at whole groups of voters — including Blacks, Latinos and Jews — who might be tempted to vote for Harris, saying, they “got to have (their) head examined.”

But Julian Zelizer, a Princeton University political scientist, sees Trump’s aggressive rhetoric as part of a deliberate campaign strategy.

Enjoying a notoriety that far outshines his Democratic rival, Trump’s “strategy is always that the party will unite around him, the anti-Trump defectors will be limited in number, and trying to appeal to the center is meaningless,” Zelizer told AFP.

‘Young men’ vs. ‘little old ladies’

Trump’s diatribes have long drawn the sort of non-stop coverage that leaves rivals gasping for media attention.

At the same time, his aggressive, macho rhetoric has helped him extend his appeal to a group he had not previously targeted: young men.

Trump has made videos with stars of the Mixed Martial Arts world or with crypto-currency influencers, and granted interviews to young podcasters who crack up when he imitates foreign leaders, rolls out his favorite nicknames or offers his most barbed insults.

As part of his charm offensive, he recently sat down for a lengthy interview with Joe Rogan, a popular podcaster known for his virile, combative, anti-politically-correct style.

“I think it’s a smart strategy for Trump to be going after low-propensity voters,” said Jennie Sweet-Cushman, a political scientist at Chatham University.

“But you know, the odds that they’re going to turn out is not as good as if he was betting on little old ladies” — who may be both offended and mobilized to vote by Trump’s increasingly violent rhetoric.