Mr Trump, according to betting odds, had been ahead in the race for the Republican nomination in 2024 but had not been on odds for a win in the election.
However, recent odds byBetfair Exchange found Mr Trump is now 4.8 to win in 2024. Mr Biden, meanwhile, was at 5.1 after falling behind his own vice president, Kamala Harris, in the presidential tie-up.
Although neither Mr Trump nor Mr Biden have formally announced a run in 2024, it is unusual for a sitting president not to take a second run at the White House. There has also been speculation that Ms Harris will run instead of her boss.
That comes despite both men being septuagenarians, and Mr Biden turning 82 — making him an octogenarian — before Inauguration Day in 2025.
Mr Trump would be 78, and almost half a year older than Mr Biden was in January. Vice President Harris would be 60, and a similar age to former president Harry Truman when he was inaugurated in 1945.
Barack Obama, in comparison, was 47 at the time of his 2009 inauguration and among the youngest ever US presidents.
Mr Trump, speaking at a rally in Iowa last Saturday, again hinted at another run in 2024 and falsely alleged that Democrats “used Covid in order to cheat and rig” the 2020 race.
The so-called “Big Lie” about his 2020 election loss has been a running theme since before Mr Biden assumed office in January, and after Mr Trump lost the race fairly.
His odds for winning in 2024 were as low as 21.0 in the wake of his second impeachment trial and alleged incitement of a riot on the US Capitol that left five people dead on 6 January.
Republicans, after attacking Mr Trump for the chaos, have largely folded and have followed his lead since the riot. Betting odds suggest he would win a Republican nomination contest.
Mr Trump told right-wing TV network Real America’s Voice last month that “a bad call from a doctor or something” would be something that stopped him from running in 2024.
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