Barron Trump makes US election campaign rally debut as father Donald tells 18-year-old: 'Welcome to the scene'

Donald Trump’s 18-year-old son Barron made his US election campaign rally debut, with his father telling him “welcome to the scene”.

The former US president, 78, introduced his son to the crowd as he hosted thousands of supporters at his golf club in Doral, Florida.

“This is the first time he’s ever done it,” he said, as he looked for his son in the crowd. “Where is Barron? Stand up. Look at him! ... You’re pretty popular. He may be more popular than Don and Eric.

“We gotta talk about this. Hey, Don, we’ve gotta talk about this huh?”.

The presumptive Republican nominee in November’s presidential election said “welcome to the scene, Barron,” saying his youngest son “had such a nice, easy life - now it’s a little bit changed” to raucous cheers.

He attacked Joe Biden in his speech over the president’s poor performance in their presidential debate on June 27 - that has led to calls within the Democrats for Mr Biden to be replaced as their candidate.

“Our victory was so absolute that Joe’s own party now wants him to throw in the towel and surrender the presidency after a single 90-minute performance,” Trump said Tuesday night. “They want `Crooked Joe’ out of the race. It’s a shame the way they’re treating him. But don’t feel sorry for him. He’s a very bad guy.”

Trump also attacked vice president Kamala Harris with more specifics than usual. She has become a focus of the former president and his allies as speculation has mounted that she would replace Biden as the Democratic nominee. Trump called her “Laughing Kamala,” and referred to the “Biden-Harris administration,” rather than just pinning actions on Biden as he had for months, and blamed Harris for the White House’s immigration policies.

“Despite all the Democrat panic this week, the truth is, it doesn’t matter who they nominate because we are going to beat any one of them in thundering landslides and this November’s going to be amazing,” he said.

Trump also teased the expected announcement of his Republican running mate with one of the top contenders, Florida Senator Marco Rubio, in attendance.

Rubio, a Miami native and one of the contenders for the vice presidential post, was among the Florida politicians who spoke at the event.

At one point, Trump marvelled at the number of reporters in attendance and said, “I think they probably think I’m going to be announcing that Marco is going to be vice president.”

Later, when he talked about his pledge to make tips tax-free, he remarked that Rubio “may or may not be there to vote for it.”

Rubio, the son of Cuban immigrants, is seen as a potential running mate who could help Trump as he tries to secure support from Hispanic Americans, a point the senator emphasized in his remarks as he switched several times in his remarks to Spanish.

The senator did not openly acknowledge any of the speculation about him joining Trump as a running mate. He instead attacked not only Biden, whom he called “the figurehead of a left-wing government, shadow government,” but Harris, whom he would need to debate head-on if he’s chosen for Trump’s ticket.

Rubio referred to Harris not by name at first but called her Biden’s “replacement” and “a real-life, verified left-winger.” At another point in his remarks, he mocked the way Harris laughs.

He notably seemed to insert himself into Trump’s signature “Make America Great Again” slogan by saying: “Together, we’re not just going to make it great again. We elect this man as president, we will make together America greater than it has ever been.”

James Singer, a spokesperson for Biden's campaign, responded to Trump with a series of challenges, saying in a statement: "We'd challenge Donald Trump to create jobs, but he lost 3 million. We'd challenge Donald Trump to stand up to Putin, but he bent the knee to him. We'd challenge Donald Trump to follow the law, but he breaks it."