Biden scrambles after Trump shooting up-ends campaign

US President Joe Biden's re-election campaign is scrambling for a new strategy after an assassination attempt on Republican rival Donald Trump in western Pennsylvania.

The campaign has called off attacks on the former president for now.

Biden is set to address the American public on Sunday afternoon after a Situation Room briefing on Trump rally shooting.

Within hours of Saturday's shooting, Biden's campaign was pulling down television ads and suspending other political communications, including those that had highlighted Trump's May conviction in New York state court on felony charges relating to hush money paid to a porn star to avert a sex scandal before the 2016 US election.

Rather than attacking Trump in the coming days, the White House and the Biden campaign will draw on the president's history of condemning all sorts of political violence including his sharp criticism of the "disorder" created by campus protests over the Israel-Gaza conflict, according to campaign officials, speaking on condition of anonymity.

Biden's advisers had hoped to tamp down recent calls from some of his fellow Democrats and others that he step aside and let another candidate represent the party in the November 5 election, sharpening his focus on the dangers he has said Trump presents to US democratic norms and reproductive rights as well as Trump's false statements that he won the 2020 election.

"This changes everything," one campaign official said of the assassination attempt.

"We're still assessing. Making the case against Trump, drawing that split screen, will get much harder."

"The president is trying to lower the temperature," the official added.

The Biden campaign officials said they expect that the assassination attempt will lower the pressure from congressional Democrats for Biden, 81, to step aside in the race amid concerns about his fitness for office.

Some Democrats in the House of Representatives and Senate have publicly called upon Biden to drop out in the aftermath of his shaky performance in a June debate against Trump.

Biden's planned trip on Monday to the Lyndon B. Johnson presidential library in Austin, Texas - where he was expected to speak on the landmark Civil Rights Act that Johnson signed into law in the 1960s and criticise Trump's attacks on immigrants and American diversity - is under review and may be cancelled, the officials said.

Because the shooting happened in the election battleground state of Pennsylvania, which Biden won over Trump in 2020 by a narrow margin, the incident could be especially impactful, according to some political strategists, by increasing Republican turnout by voters sympathetic to Trump.

"This doesn't guarantee that Trump flips Pennsylvania," Republican pollster Frank Luntz wrote on social media.

"But the long and winding road for Joe Biden just became even longer and windier. Just as what happened to George Floyd had a lasting impact on tens of millions of Americans, the shooting of Donald Trump will be significantly consequential in a way the shooter never intended."

Floyd is the black man who was killed by a white police officer in Minneapolis in 2020, a murder that prompted protests in many US cities and abroad.

Other Democratic candidates running this year are also rethinking their plans to focus on the dangers they have said Trump poses if elected.

"The real question is whether in two weeks we can go back and declare Trump a threat to the country. That was our playbook, and it's fair, but unclear how much of our spurs were taken off," said a Democrat involved in a Senate campaign, speaking on condition of anonymity.

with AP