Biden,however,also has his share of challenges heading into the election,withrecord low approval ratings,widespread dissent over his stance on Gaza,and voters – including many Democrats – believing the 81-year-old is too old and unfit to serve another term.

“Wait,NOTHING about the economy,the southern border,crime in our streets,or the global chaos created by Joe Biden,” Trump campaign adviser Jason Miller said on X,formerly known as Twitter. “Biden knows he’s in a tail spin and there’s nothing he can do about it.”

Trump,meanwhile,spent the day holding rallies in Iowa ahead of the Republican presidential primaries,which begin with the Iowa caucuses on January 15.

Despite facing 91 criminal charges and multiple trials,the 77-year-old is currently the overwhelming frontrunner to win his party’s nominationahead of his two main rivals,Florida Governor Ron DeSantis and former UN ambassador Nikki Haley.

In another sign that this year’s election will play out largely in the legal system,the US Supreme Court on Saturday (AEDT) agreed toa request by Trump to review Colorado’s contentious decision to remove him from its Republican primary ballot.

Colorado’s top court had ruled last month that Trump had incited an insurrection and was therefore disqualified from office under Section 3 of the 14th Amendment,prompting him to appeal. He has long insisted he did not incite an insurrection,and told supporters on the campaign trail that he would pardon many of the January 6 rioters if he won another term in the White House.

In his speech,Biden hit out atTrump’s actions on the day of the Capitol attack,and his ongoing election denialism.

“Let’s be clear:Trump exhausted every legal avenue available to him to overturn the election - every one - but the legal path just took Trump back to the truth:that I had won the election,and he was a loser,” Biden said.

“Today,I make this sacred pledge to you. The defence,protection and preservation of American democracy will remain as it has been:the central cause of my presidency. As we begin this election year,we must be clear,democracy is on the ballot. Your freedom is on the ballot”.

Speaking in Sioux Centre,Iowa,Trump hit back by accusing Biden of “staging a pathetic,fearmongering campaign”. He also claimed it was the Democrats who had damaged democracy by “weaponising the government” and using federal law authorities to thwart his campaign.

Earlier,New York state Attorney-General Letitia James asked the judge overseeing Trump’s civil fraud trial to fine him $US370 million ($552 million) and prevent him from ever doing business again in that state.

Further elements of the New York case – in which Trump,his sons,and the wider Trump Organisation have been found to havemassively exaggerated the value of their properties to secure favourable loans – are to be decided within weeks.

Trump has consistently denied wrongdoing and has accused James and Judge Arthur Engoron of being Democratic Party hacks trying to interfere with his election prospects.

“Our founding fathers would be turning in their graves if they could see this,” Trump said. “No American should be okay with a political party being weaponised against their enemies.

“How much longer can we allow this to happen in our country? And all of this is being done because we’re beating them so badly at the polls.”

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