Jogging to the podium, US President Joe Biden didn't betray any concern that his son had just been indicted on gun charges -- and nor did the audience.

The crowd cheered and whooped as he arrived at a college in Largo, Maryland to give a speech aimed at wrestling the narrative away from his recent troubles and back to his "Bidenomics" agenda.

Afterwards they crowded round to try to shake the 80-year-old's hand or take selfies, the worries about polling, impeachment inquiries, age and criminal charges briefly forgotten.

"That's a distraction, that's political distraction," said Susanna Anderson, 49, when asked about the issues facing the president.

Wearing a blue T-shirt made by her own small business saying "The VP Looks Like Me" -- a reference to Vice President Kamala Harris, who is Black -- the mother of two showed a picture she took with Biden.

"When they have an election coming up they have to throw something and see if it sticks. I'm not focused on that," she added.

The night before, Biden used the exact same words -- "not focused" -- as he brushed aside the impeachment probe launched by Republican lawmakers over Hunter Biden's business dealings.

He made no mention on Thursday of the fact that his son had been indicted for buying a gun when he was using drugs, casting a new shadow over Biden's 2024 re-election campaign.

- 'Tip of the iceberg' -

What about his age, a frequent lightning rod for criticism by Republicans against America's oldest president?

"Did you see him run up the stage? I'm not worried about that," said Enicia Porter, 34. "He has a firm handshake... He reminds me of my grandfather."

The White House has been keen to get Biden out on the campaign trail again, amid a sense that his stewardship of America's economic recovery is not registering in the polls.

For his speech at Prince George's Community College in Largo, given against a backdrop of American flags and "Bidenomics" signs, Biden introduced a new line of attack: MAGAnomics.

The idea is to portray all Republicans as followers of former president Donald Trump -- known for his "Make America Great Again" (MAGA) slogan -- and highlight Trump's economic failures.

Biden also sought to blame them for the threat of a looming government shutdown at the end of this month.

But was the message getting through here, to the audience of around 200 local people and college students in a dormitory town half an hour's drive from the White House, let alone to millions of voters?

"I think this was a good tip of the iceberg," said Porter, a local chapter treasurer of Student Veterans of America. "But I'm going to need more concrete follow up."

Porter said she had asked Biden about housing in particular "and he nodded and said we have a whole plan."

- 'Papa Joe' -

Biden still had work to do to convince the electorate, agreed Don Pruett, 68, director of planning at the college. 

The president's speech is "going to plant the seeds and over the course of time it needs to be nurtured," he said. "We need to see the fruits."

Susanna Anderson, the blue T-shirt wearer, however said Biden was "getting the message through to the people who need to hear" -- including her sister, whom she said had just had her student loans forgiven by the Biden administration, a policy opposed by Republicans.

Biden hammered that message home repeatedly, slamming the lectern at one point as he reeled off what he said were Republican plans to cut spending.

He also lashed out at the record of Trump -- who faces a string of criminal charges including over election interference, and whom he will likely face in a rematch in 2024 -- and warning darkly that "democracy's under attack."

With a gruelling campaign ahead, Pruett reckoned Biden faced a "tough road" for re-election.

But he added: "There's so much chaos on the other side... if he continues to be stable, Papa Joe will be there."

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