Trump isn’t expected to announce a third run for president in his Washington speech, according to advisers. But the notoriously mercurial ex-leader could change his mind on the way into town from the airport.

A day before he speaks, his former vice-president, Mike Pence, will deliver remarks of his own, highlighting the rivalry that has developed between the two men after Trump lambasted Pence for refusing to participate in his scheme to overturn his re-election defeat.

In the aftermath of his defeat and the chaos that unfolded at the Capitol on January 6, Trump slipped out of Washington in disgrace the morning of President Joe Biden’s inauguration.

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His return – at a time when Biden is notching the lowest approval rating of his presidency and contending with foreign crises and domestic anger over inflation and culture war issues – has fanned speculation about what’s considered an all-but-inevitable campaign announcement.

“He loves that the news is about whether he’s ready to announce, when he’s going to announce,” said Barry Bennett, a Republican strategist who worked on Trump’s 2016 campaign. “He loves all of the media speculation and he doesn’t mind a fight, but when you actually declare you have to make FEC filings.”

Bennett said he believes Trump will hold off to avoid triggering federal election law requirements and limits on fundraising.

Trump has raised US$137 million since the start of 2021 through the end of June, Federal Election Commission records show, with the bulk coming from his loyal army of small-dollar donors.

Save America, his political action committee, has US$103 million in the bank, though contribution limits would bar him from using more than US$5,000 of that total for his presidential campaign.

Some congressional Republican leaders would prefer for Trump to hold off on an announcement to avoid complicating their message ahead of the November midterm elections, in which the Republican Party is expected to take control of the House and possibly the Senate.

Regardless of when it happens, US voters are learning shocking details about the behaviour of the president and his closest aides before and during the Jan. 6 insurrection. It will raise the question of how his popularity has ebbed outside of his devoted base.

About 56 per cent of Americans hold an unfavourable view of the former president and less than 41 per cent hold a favourable view, according to an analysis of polling by FiveThirtyEight. That 15-point gap has almost tripled since late March, before the January 6 committee began holding public hearings to reveal its findings about efforts by Trump and his associates to overturn his re-election defeat.

Still, 69 per cent of Republican voters would like to see Trump run again in 2024, according to a Quinnipiac University poll this month. By contrast, 54 per cent of Democrats would prefer someone other than Biden as their 2024 nominee.

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His remarks at the America First summit will be Trump’s highest-profile speech since leaving office, just blocks from the White House where his successor is recuperating from Covid-19.

The America First summit will feature a number of Republican luminaries in addition to Trump, including House Minority Leader Kevin McCarthy, who has sought to mend his relations with the former president after criticising him in the days after the Capitol riot.

Notably, however, some potential rivals for the party’s 2024 nomination won’t be in attendance, including Florida Governor Ron DeSantis, who polls currently show would be Trump’s most potent challenger.

And Trump’s speech will be pre-empted by Pence, who was expected to deliver remarks to another Republican interest group, the Heritage Foundation, on Monday.

Pence was among Trump’s top loyalists until January 6, when he rebuffed the president’s demands that he refuse to accept Electoral College votes from states where Trump and his allies claimed fraud had marred the results.

Pence carried out his constitutionally prescribed duties, then hid within the Capitol as Trump’s supporters invaded the building. The former vice-president is popular among conservatives, especially evangelical Christians, and is regarded as likely to make his own run for the presidency in 2024.

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Trump’s advantage over potential rivals such as DeSantis has significantly eroded over the course of the committee hearings, one Republican strategist said. The person asked not to be identified to candidly assess Trump’s prospects.

The US hasn’t seen a presidential candidate make a bid for a third consecutive major-party nomination in generations. Only one other president, Grover Cleveland, has served two non-consecutive terms, each in the late 19th century.

Other potential Republican candidates in 2024 include Trump’s former secretary of State Mike Pompeo and former UN ambassador Nikki Haley, as well as senators Rick Scott of Florida and Ted Cruz of Texas. It’s not yet clear how broad a field will emerge if Trump runs.

A crowded Republican presidential primary would benefit Trump, who still has a grip on more than a third of the party’s voters, the strategist said.

There’s a general sense within the party that there’s an opening emerging for a challenger. But because Trump may focus his attacks most sharply on the first person to declare his or her candidacy, some rivals may try to delay their announcements.