Speaking at two events in Iowa, Trump also sought to counter growing concern among Democrats and some Republicans that his potential return to the White House posed a threat to democracy.

Even as he faces criminal charges over his efforts to reverse his 2020 loss, Trump attempted to flip the script and paint the winner, President Joe Biden, as a dangerous autocrat, calling him a communist, fascist and a tyrant.

A spokesperson for Biden's re-election campaign said Trump's comments portraying Biden as a threat to democracy were an attempt to divert the public's attention from his own problems.

Looking ahead to next year's general election, Trump said it was important to scrutinize the vote in the battleground states likely to determine the outcome. He singled out the biggest cities in Michigan, Pennsylvania and Georgia - all Democratic strongholds at the center of the blizzard of false voter fraud claims made by Trump and his allies three years ago.

"So the most important part of what's coming up is to guard the vote. And you should go into Detroit and you should go into Philadelphia and you should go into some of these places, Atlanta," Trump said in Ankeny, a suburb of Des Moines.

Trump's comments foreshadow what is likely to be a contentious election in November 2024. Despite the failure of dozens of lawsuits filed by Trump and his allies challenging the 2020 outcome, Trump continues to claim, without evidence, that he lost to President Joe Biden due to fraud.

Trump did not specify who he was asking to "go into" the battleground-state cities. A campaign aide, when asked to clarify, said he was referring to poll-watchers and volunteers whose objective would be to ensure a secure election.

That would mesh with plans outlined by the Republican National Committee, which is aiming to recruit and train tens of thousands of poll workers and watchers in states that are hotly contested because their voting preferences could swing either to Republicans or Democrats.

'VOLATILE PERIOD' FOR DEMOCRACY

The comments by Trump, president from 2017 to 2021, come amid growing scrutiny over his recent rhetoric on the campaign trail, which has included referring to his political enemies as "vermin," a word some historians said echoed the language of Nazi Germany.

Timothy Naftali, a senior research scholar at Columbia University's School of International and Public Affairs, said Trump's comments calling for scrutiny of elections in large Democratic-controlled cities were concerning because he made them while seeking to undermine trust in U.S. elections.

"We are in a very volatile period in our democracy," Naftali said. "If he is seeking to increase trust in our system, he should be more explicit. But what he said today was in the context of his mistrust of our system."

In recent weeks Biden's re-election campaign has more aggressively gone after Trump, highlighting his mounting legal troubles and likely policies it argues would hurt the economy and damage the foundations of democracy. Trump, for instance, has vowed to use his power to imprison his political enemies.

"Donald Trump’s America in 2025 is one where the government is his personal weapon to lock up his political enemies,” campaign spokesman Ammar Moussa said in response to Trump's Iowa remarks.

"After spending a week defending his plan to rip health care away from millions of Americans, this is his latest desperate attempt at distraction — the American people see right through it and it won’t work.”

Trump is facing four criminal trials, including two accusing him of seeking to subvert the 2020 election, helped by a mob of his supporters who ransacked the Capitol on Jan. 6, 2021.

At an event in Cedar Rapids, Trump's campaign passed out signs reading 'BIDEN ATTACKS DEMOCRACY'. During his speech Trump repeated his unsubstantiated claim that Biden was using the Justice Department to go after him, among other alleged transgressions making Biden the threat to democracy.

"Joe Biden wants to make this race a question of which candidate will defend our democracy and protect our freedoms," Trump said. "This campaign is a righteous crusade to liberate our republic from Biden and the criminals."

Also on Saturday, Trump doubled down on comments made a few days earlier indicating he wanted to make significant changes to the Affordable Care Act, known as Obamacare, calling the healthcare insurance program used by millions of Americans "a disaster." He did not provide specifics.