FORMER US PRESIDENT Donald Trump has said he will officially mount a third campaign for the White House, launching an early start to the 2024 contest.

The announcement comes just a week after an underwhelming midterm showing for Republicans and will force the party to decide whether to embrace a candidate whose refusal to accept defeat in 2020 pushed American democracy to the brink.

“In order to make America great and glorious again, I am tonight announcing my candidacy for president of the United States,” Trump said to an audience of several hundred supporters, club members and gathered press in a chandeliered ballroom at his Mar-a-Lago club in Florida.

He was flanked by more than 30 American flags and banners that read: “Make America Great Again.”

“America’s comeback starts right now,” he said, formally beginning the 2024 Republican primary.

Another campaign is a remarkable turn for any former president, much less one who made history as the first to be impeached twice and whose term ended with his supporters violently storming the US Capitol in a deadly bid to halt the peaceful transition of power on 6 January 2021.

Trump enters the race in a moment of political vulnerability. He hoped to launch his campaign in the wake of resounding GOP midterm victories, fuelled by candidates he elevated during this year’s primaries.

Instead, many of those candidates lost, allowing Democrats to keep the Senate and leaving the GOP with a path to only a bare majority in the House.

Far from the undisputed leader of the party, Trump is now facing criticism from some of his own allies who say it is time for Republicans to look to the future, with Florida Governor Ron DeSantis emerging as an early favourite White House contender.

Still, the former president remains deeply popular with the GOP base, even as Mr DeSantis and other Republicans, including former vice president Mike Pence, are taking increasingly public steps toward campaigns of their own, raising the prospect that Trump will have to navigate a competitive GOP primary.

Trump is also launching his candidacy amid a series of escalating criminal investigations, including several that could lead to indictments.

They include the probe into dozens of documents with classified markings that were seized by the FBI from Mar-a-Lago and ongoing state and federal inquiries into his efforts to overturn the results of the 2020 presidential election.

But Trump, according to people close to him, has been eager to return to politics and try to halt the rise of other potential challengers.

Aides have spent the last months readying paperwork, identifying potential staff and sketching out the contours of a campaign that is being modelled on his 2016 operation, when a small clutch of aides zipping between rallies on his private jet defied the odds and defeated far better-funded and more experienced rivals by tapping into deep political fault lines and using shocking statements to drive relentless media attention.

Trump returned to that dark rhetoric in his speech last night, painting the country under President Joe Biden in apocalyptic terms, describing “blood-soaked streets” in “cesspool cities” and an “invasion” at the border and earning cheers as he vowed to execute those convicted of selling drugs.

“We are a nation in decline,” he said. “We are here tonight to declare that it does not have to be this way.”

And while Trump spoke before a crowd of several hundred, notably missing were many longtime supporters including previous campaign managers, aides and his daughter Ivanka, who released a statement saying that she does not plan to be involved in politics.

“While I will always love and support my father, going forward I will do so outside the political arena,” she said in statement.

Trump’s candidacy poses profound questions about America’s democratic future. The final days of his presidency were consumed by a desperate effort to stay in power, undermining the centuries-old tradition of a peaceful transfer.

And in the two years since he lost, Trump’s persistent — and baseless — lies about widespread election fraud have eroded confidence in the nation’s political process.

Federal and state election officials and Trump’s own attorney general have said there is no credible evidence the 2020 election was tainted. The former president’s allegations of fraud were also roundly rejected by numerous courts, including by judges Trump appointed.

But that did not stop hundreds of midterm candidates from parroting his lies as they sought to win over his loyal base and score his coveted endorsement.

While some Republicans with presidential ambitions have long ruled out running against Trump, others appear ready to challenge him. They include Mr DeSantis, whose commanding re-election as governor last week was a bright spot for Republicans this cycle.

If he was ultimately successful, Trump would be just the second US president in history to serve two non-consecutive terms, following Grover Cleveland’s wins in 1884 and 1892.

President Joe Biden responded to Trump’s announcement by saying the Republican “failed” his country while in office.

“Donald Trump failed America,” Biden said in a tweet from Bali, where he was attending the last day of the G20 summit.

This accompanied a video compilation saying Trump presided over “rigging economy for rich”, “attacking health care”, “coddling extremists”, “attacking women’s rights” and “inciting a violent mob” to try to overturn his 2020 election loss to Biden.

Later, while participating in a ceremonial mangrove planting with other G20 leaders, reporters asked Biden and French President Emmanuel Macron if they had reactions to the Trump announcement.

The two looked at each other briefly before Biden said “not really”, while Macron remained silent.

Additional reporting by AFP