Trump walked into the venue in downtown Milwaukee with a thick bandage over the ear as the crowd chanted "Fight! Fight! Fight" and pumped their fists, a reference to his reaction in the moments after he was wounded.
The former president appeared moved by the response as he stood in a box with some of his children and US Senator JD Vance, Trump's choice for running mate announced earlier in the day.
Trump announced Senator JD Vance as his chosen running mate, despite the senator's past criticism. (AP PHOTO)
Trump is due to formally accept the party's nomination in a prime-time speech on Thursday and will face Democratic President Joe Biden in the November 5 election.
During the evening session, one speaker after another blamed Biden's economic policies for inflation that has kept prices higher, even as it has eased sharply since peaking in June 2022 in the wake of the coronavirus pandemic.
Senator Tim Scott, who briefly ran against Trump for the nomination, said divine intervention spared Trump's life.
"Our God still saves," Scott said. "He still delivers and he still sets free. Because on Saturday the devil came to Pennsylvania holding a rifle, but an American lion got back up on his feet and he roared!""
Vance, 39, was a fierce Trump critic in 2016 but has since become one of the former president's staunchest defenders, embracing his false claims that the 2020 election was marred by widespread fraud.
Biden told reporters at Joint Base Andrews in Maryland that Vance is 'a clone of Trump on the issues,' while Democrats assailed Vance's record on reproductive rights.
Opinion polls show a close race between Trump, 78, and Biden, 81, though Trump leads in several swing states that are likely to decide the election. Trump has not committed to accepting the results of the election if he loses.
Trump is vowing to emphasis national unity, after the attempt on his life at a campaign rally. (AP PHOTO)
The head of the main fundraising super PAC supporting Trump's campaign, Taylor Budowich, said on X that MAGA Inc had raised more than $50 million on Monday.
Billionaire Elon Musk is planning to donate around $45 million a month to a new pro-Trump super PAC, the Wall Street Journal reported.
After the assassination attempt, Trump said he was revising his acceptance speech to emphasise national unity, rather than highlight his differences with Biden.
"The speech will be a lot different, a lot different than it would've been two days ago," Trump told the Washington Examiner.
The four-day convention opened hours after Trump secured a major legal victory when a federal judge dismissed one of his criminal prosecutions.
US District Judge Aileen Cannon threw out federal charges against Trump for retaining classified documents after leaving the White House.
"This dismissal of the Lawless Indictment in Florida should be just the first step, followed quickly by the dismissal of ALL the Witch Hunts," Trump said on Truth Social on Monday, also referencing the prosecutions of hundreds of his supporters who stormed the US Capitol on January 6, 2021.
The shooting attempt on Trump's life immediately altered the dynamics of the presidential campaign, which had been focused on whether Biden should drop out due to concerns about his age and acuity following a halting June 27 debate performance.
Biden has cast Trump as a threat to US democracy, comments that some Republicans say helped foster an atmosphere that prompted the shooting even though authorities have yet to determine the motive for the assassination attempt. The gunman himself was shot dead.
Trump has frequently turned to violent rhetoric in campaign speeches, labelling his perceived enemies as "vermin" and "fascists."
Following Saturday's shooting, Biden sought to lower the temperature after months of heated political rhetoric.
In an interview with NBC News on Monday, Biden said it was a "mistake" to tell donors last week it was "time to put Trump in the bullseye" but noted that Trump has often used incendiary words.
Biden has ordered an independent review of how the gunman, who killed a spectator, could have come so close to killing Trump.
Congressional investigators also sought to question the head of the US Secret Service, which is responsible for protecting the former president.
with AP