"I'll probably start off by saying, 'As I was saying ...'" the Republican presidential nominee has joked about a speech cut short when a bullet struck Trump's ear and he was whisked off stage - fist aloft - with blood dripping across his face.
Trump's running mate, Ohio senator JD Vance, also will be on hand at the Butler Farm Show grounds on Saturday, as will billionaire Elon Musk, as the campaign elevates the headline-generating potential of his return with just 30 days to go in their tight campaign against Democratic Vice-President Kamala Harris and Minnesota Governor Tim Walz.
Donald Trump was whisked to safety after a bullet struck his ear on stage in Pennsylvania. (AP PHOTO)
The campaign is predicting tens of thousands of people will attend what is being pitched as a "tribute to the American spirit".
"President Trump looks forward to returning to Butler, Pennsylvania to honour the victims from that tragic day," Trump campaign spokeswoman Karoline Leavitt said.
Trump will use event to remember Corey Comperatore, a volunteer firefighter struck and killed at the July 13 rally, and to recognise the two other rallygoers injured, David Dutch and James Copenhaver.
They and Trump were struck when 20-year-old shooter Thomas Matthew Crooks, of Bethel Park, Pennsylvania, opened fire from an unsecured rooftop nearby before he was fatally shot by sharpshooters.
How Crooks managed to outmanoeuvre law enforcement that day and scramble on top of a building within easy shooting distance of the ex-president is among myriad questions that remain unanswered about the worst Secret Service security failure in decades.
Another is his motive, which has never been determined.
Butler County District Attorney Rich Goldinger told WPXI-TV this week that "everyone is doubling down on their efforts to make sure this is done safely and correctly".
Mike Slupe, the county sheriff, told the station he estimates the Secret Service - which has undergone a painful reckoning over its handling of two attempts on Trump's life - was deploying "quadruple the assets" it did in July.
Butler County, on the western edge of a coveted presidential swing state, is a Trump stronghold.
He won the county with about 66 per cent of the vote in both 2016 and 2020.
Three months later, townspeople are divided over the value of his return.
Heidi Priest, a Butler resident who started a Facebook group supporting Harris, said Trump's last visit fanned political tensions in the city.
"Whenever you see people supporting him and getting excited about him being here, it scares the people who don't want to see him re-elected," she said.
But Trump needs to drive up voter turnout in conservative strongholds like Butler County, an overwhelmingly white, rural-suburban community, if he wants to win Pennsylvania in November.
Harris, too, has targeted her campaign efforts at Pennsylvania, rallying there repeatedly as part of her aggressive outreach in critical swing states.
