Donald Trump made a surprise appearance on the first night of the Republican Party convention Monday, one day before he was to be formally nominated as the party's presidential candidate.
"We're going to win, we're going to win so big," Trump said, basking in cheers from the delegates as he appeared on a darkened stage silhouetted against a lighted doorway.
Trump appeared to introduce wife Melania, who was giving the main speech on the first night of the four-day convention.
Melania Trump declared her husband "ready to serve and lead this country as the next president of the United States."
She was the first of several family members to speak as the campaign seeks to reintroduce its presidential candidate to voters both inside and outside the conservative party.
"He is tough when he has to be, but he is also kind and fair and caring," she said as the campaign tries to humanize the billionaire businessman. "This kindness is not always noted, but it is there for all to see. That is one reason I fell in love with him to begin with."
The theme of Monday evening's speeches was Make America Safe Again, with speaker after speaker painting Trump as a tough leader who would protect Americans by taking on Islamist terrorists, illegal immigrants and criminals.
"Today our allies no longer trust us, our adversaries no longer fear us, and our enemies are plotting against us. This did not happen by accident, it happened by design," Congressman Mike McCaul, who heads the House Homeland Security Committee said, pointing to the work of President Barack Obama and his former secretary of state and would-be successor Hillary Clinton.
"For years they presided over America's retreat. And the consequence is clear: Leading from behind has led us into danger."
The campaign sought to draw a contrast with presumptive Democratic nominee Clinton by prominently featuring the mother of one of the US citizens killed in the 2012 terrorist attack on the US consulate in Benghazi, Libya, during her tenure as secretary of state.
Several speakers described how their family members had been killed by illegal immigrants or in an attack at what they described as the unsecured US border with Mexico, where Trump has vowed to build a wall to halt illegal crossings.
Indiana delegate Dana Carroll told dpa she liked Trump's "brash attitude" and said she though he would "lead us back to where we should be."
The Trump campaign had to win over not just US voters at large, but even many of the party faithful within the arena, as the party remains divided after a fractious primary process that saw the unexpected rise of outsider Trump.
An analysis by Pew Research Centre found that most Republicans had changed their minds at least once in their choice for president. As late as April some 44 per cent did not support him, but now 88 per cent do.
A minority of delegates had held out hope until Monday that they could force the convention to consider an alternate nominee, in a throwback to earlier days when the party's delegates had a greater sway than under the current system of state-by-state primary elections.
The Trump campaign has dismissed the push, and chose vice presidential candidate, Indiana governor Mike Pence, to seek party unity with more traditional Republicans.
"Of course he's going to win: This is a Trump convention," campaign chairman Paul Manafort said. "This party is united."
Chairman Reince Preibus called the Republican National Convention into session as delegates from across the United States prepare to nominate Trump for the November general elections.
Events began Monday as delegates approved the rules for the proceedings and a party platform that bears the distinct mark of Trump, backing away from the Republicans' strong support for free trade and calling for the construction of a wall along the US-Mexican border.
The traditionally staid business proceedings however saw early fireworks as a small group of Republicans opposed to Trump's candidacy tried unsuccessfully to disrupt the proceedings and call for delegates to pick an alternate candidate.
The party's 2,472 delegates are to officially put forward the presidential nominee on Tuesday. The winner needs 1,237 delegates, and Trump cleared that hurdle in May.