CHARLOTTE - Donald Trump made a rare act of contrition on Thursday, saying he regretted offending people with his harsh way of speaking.

Trump made the gesture at his first rally since ordering a shakeup in his campaign to save his struggling bid as Republican candidate for the US presidency.

"Sometimes in the heat of debate and speaking on a multitude of issues, you don’t choose the right words or you say the wrong thing," Trump told a rally in Charlotte, North Carolina.

"I have done that. And believe it or not, I regret it," he said, drawing laughs and applause from the crowd.

"I do regret it. Particularly, where it may have caused personal pain."

He added: "Too much is at stake for us to be consumed with these issues, but one thing I can promise you this, I will always tell you the truth."

The New York billionaire’s multiple self-inflicted wounds of late have left him trailing in virtually every battleground state. One of the biggest was when he clashed repeatedly with the parents of an Army captain killed in Iraq.

Critics accused him last week of inciting violence against his Democratic opponent Hillary Clinton in a remark about the right to bear arms, and media reports have swirled about a campaign in crisis and a candidate apparently incapable of reeling in crass remarks.

Clinton leads Trump 47 per cent to 41.2 per cent, according to the Real Clear Politics polling average, following weeks of errors that have alienated establishment Republicans and seen his own supporters tear their hair out.

Campaign staff shakeup

On Wednesday, Trump appointed right-wing news executive Stephen Bannon CEO and promoted pollster Kellyanne Conway to campaign manager.

The change was seen as a demotion for campaign chairman Paul Manafort, who has been pushing Trump, among other changes, to use a teleprompter when he gives speeches as a way to stay on message -- and not ad-lib himself into saying something offensive or wrong.

The choice of Bannon, however, was seen as Trump’s way of thumbing his nose at Republican leaders who have been urging him to tone down the shoot-from-the-hip style of speech he used effectively in the primaries.

On Thursday, Trump did speak with a teleprompter and veered from the invisible screens only to hammer away at a given point he wanted to make.

On substantive issues, he reached out to US minorities, in particular blacks.

"Nearly four in ten African-American children are living in poverty. I will not rest until children of every color in this country are fully included in the American Dream," Trump said.

"If African-American voters give Donald Trump a chance by giving me their vote, the result for them will be amazing," he said.

He stressed his standard campaign pillars of building a wall along the border with Mexico, keeping out undocumented foreigners and opposing international trade accords.

He depicted himself as an agent of change compared to Clinton, whom he dismissed as an old-fashioned Washington insider. -- AFP