(AFP) - Donald Trump has won the US presidential election, media said Wednesday, defeating Kamala Harris in a stunning political comeback that will send shock waves across the world.

The polarizing Republican's victory, following one of the most hostile campaigns in modern US history, was all the more remarkable given an unprecedented criminal conviction, a near-miss assassination attempt, and warnings from a former chief of staff that he is a "fascist."

"It's a political victory that our country has never seen before," Trump told a victory party in Florida.

Vice President Harris, who only entered the race in July after President Joe Biden dropped out, ran a centrist campaign that highlighted Trump's inflammatory messaging and use of openly racist and sexist tropes.

But his apocalyptic warnings about immigration and championing of isolationism found their mark with voters battered by the post-Covid economy and eager for a change from the Biden years.

The campaign pointed to a nail-bitingly close contest, but the results came surprisingly fast, delivering a crushing victory that included wins in the swing states of Georgia, North Carolina and Pennsylvania.

Trump is the first president in more than a century to win a non-consecutive second term.

He is also the only person to be elected as a convicted felon -- he will face sentencing in a New York court for fraud on November 26.

Already 78, Trump is on course to break another record as the oldest-ever sitting president during his four-year term. He will surpass Biden who is set to step down in January at the age of 82.

- Impact on foreign policy -

The US dollar surged and bitcoin hit a record high while most equity markets advanced, with traders betting on a victory for Trump as the results rolled in.

But turmoil likely lies ahead.

Trump's victory comes with his promise of radical policy shifts -- not just at home but also abroad, where his unrestrained isolationist and nationalist "America First" stance is likely to have enormous consequences.

He has repeatedly suggested he would end the conflict in Ukraine by pressuring Kyiv to make territorial concessions to Russia, and his threat of mass deportations of illegal immigrants has stirred deep concern in Latin America.

He also returns to the White House as a climate change denier, poised to dismantle his predecessor Biden's green policies and jeopardize global efforts to curb human-caused warming.

Even before Trump's stunning victory was fully confirmed, foreign leaders rushed to send congratulations.

These included longtime Trump allies, Israeli Prime Minister Benjamin Netanyahu, Indian Prime Minister Narendra Modi, and Turkish Prime Minister Recep Tayyip Erdogan.

Also messaging Trump was Ukrainian President Volodymyr Zelensky, who is predicted to see a rapid reduction in US military aid once Biden leaves office. Zelenksy said he hoped the "impressive victory" would help his country find a "just peace."

NATO's chief, Mark Rutte, said Trump, who has frequently expressed displeasure with the US-led alliance, would make it "strong."

British Prime Minister Keir Starmer joined the stream of well-wishers, while French President Emmanuel Macron vowed to join Trump in working "with respect and ambition." 

- Showman's instinct - 

For all his dark promises of political revenge against enemies at home and his criticisms of longstanding allies overseas, Trump remains famously unpredictable when it comes to matching words with actions.

His campaign rallies, filled with grievance, insults and misinformation, featured extreme rhetoric.

But he won positive coverage with viral online moments that played on his everyman appeal and his showman's instinct -- like his appearance at a McDonald's drive-thru and impromptu news conference from a garbage truck.

He campaigned on tax cuts, less regulation and the most significant increase in import tariffs in nearly a century to promote growth and boost manufacturing, despite warnings of trade wars and higher prices for US consumers.

Trump's more mainstream messaging often became overshadowed by his tendency to lurch into foul language and violent imagery. But that hard-charging style played well with his unfailingly loyal base, which sees him as a Washington outsider.

And he gained traction with his hard-line anti-immigration message and outreach to working-class voters hit by Covid-triggered inflation.

When Harris joined the race in July, replacing Biden, she soon managed to close the yawning gap Trump had opened over the president in opinion polls.

Her message of unity, focus on abortion rights and warnings of the threat Trump posed to democracy appeared to resonate, evidenced by a huge surge in fundraising that swelled her campaign war chest way beyond her rival's.

Ultimately, however, she fell short of what would have been a historic win as the first Black woman elected to the White House.

© Agence France-Presse