Donald Trump told the Republican National Convention he was "not supposed to be here," reflecting during a marathon speech on a recent attempt on his life.

His address on Thursday night came just five days after his ear was pierced by bullets fired at him by a would-be assassin during a rally in Pennsylvania.

The speech, delivered to a hushed crowd, struck in parts a sombre tone and only once mentioned the name of his rival, President Joe Biden.

His wife Melania also made a rare public appearance, joining her husband on stage with other family members.

During his 90-minute speech, there were familiar targets of Trump attacks such as undocumented migrants, Biden foreign policy and China.

But the start was very different, as he recalled the details of last Saturday's attack in Pennsylvania, describing how a bullet narrowly missed his head and grazed his ear while he turned his head to present a chart of immigration figures.

One man, Corey Comperatore, was killed in the attack, after which the suspected gunman, Thomas Matthew Crooks, was shot dead by authorities.

Mr Comperatore was honoured at a memorial service on Thursday, as major questions continue to be asked over security lapses at the event.

Trump praised the Secret Service agents who shielded him after the shots were fired, and said he was only alive to tell the story "by the grace of almighty God".

Observers said his speech was relatively subdued, in spite of the overall bombast of the evening, which included a shower of balloons and a crowd-rallying appearance from wrestling legend Hulk Hogan.

Trump had pledged to re-write his address in the wake of the attack, after which he had what he called a "very cordial" conversation with Mr Biden. The finished item was critical of the current president's policies, although he spoke his adversary's name only once during his range of attacks.

He again promised to curb illegal immigration, vowing the "largest deportation operation in the history of our country", and said he would "end every single international crisis that the current administration has created".

Trump also said he would create a version of Israel's Iron Dome missile defence system, and pledged to restore "peace, stability and harmony all throughout the world" - though he gave few details on how.

The speech concluded with a rare on-stage appearance from Trump's wife, other family members and prominent supporters. It capped off a triumphant four-day convention for Trump, during which he formally became the Republicans' nominee for president and unveiled his running mate for November.

In his debut speech in the role, that man - 39-year-old Ohio Senator JD Vance - told the convention that he was a "working-class" boy, and insisted that Trump's policies would help left-behind voters.

Among the others who made notable appearances at the convention were Mr Vance's wife Usha, as well as Trump's daughter-in-law Lara and his teenage granddaughter Kai, who gave her first public remarks.

And Trump's former rivals for the Republican nomination, Nikki Haley and Ron DeSantis, came together to voice their support for him.

Their message of party solidarity was echoed in Thursday's speech by Trump, who also spoke of working for "all of America" if he won back the White House.

In addition to the applause of his supporters at the convention, Trump has been buoyed by polling on Thursday from the BBC's US partner, CBS News.

This has suggested that Trump has assumed his clearest poll lead of the campaign so far, and is riding five points ahead of his rival, Mr Biden.

The numbers appear to further indicate that Trump's conviction last month in a New York criminal hush-money case has not dented his appeal. Pundits have suggested his survival of the assassination attempt could strengthen his image.

Trump received further good news on Monday when he learned that a Florida judge had thrown out another case against him relating to his retention of classified documents after leaving the White House in 2021. Prosecutors are likely to appeal.

Meanwhile, Mr Biden has endured a difficult week, and is currently self-isolating with a bout of Covid-19. His re-election campaign is under further scrutiny amid reported concerns about the presidential election from Barack Obama.

Mr Obama is reported by the Washington Post to have privately stated that Biden's chances of beating Trump in November are greatly diminished. Spokespeople for the former president have declined to comment.

It follows reports that former House Speaker Nancy Pelosi and the two most senior Democrats in Congress, Hakeem Jeffries and Chuck Schumer, have told Mr Biden of their own concerns. All have rejected the reports.

Mr Biden's campaign has dismissed the reported concerns of top Democrats, insisting he will remain the nominee.