The incumbent President's advanced age makes his re-election bid a historic and risky gamble for the Democratic Party, which faces a tough election map to hold the Senate in 2024.
President Joe Biden has said he will seek a second White House term in 2024, a decision that will test whether Americans are ready to give the 80-year-old Democrat, already the oldest US president ever, another four years in office.
Biden made his announcement in a slickly produced video released by his new campaign team on Tuesday, in which he declares it is his job to defend American democracy.
It opens with imagery from the January 6, 2021, attack on the US Capitol by supporters of former president Donald Trump.
"When I ran for president four years ago, I said we're in a battle for the soul of America, and we still are," Biden said. "This is not a time to be complacent. That's why I'm running for re-election."
"Let's finish this job. I know we can," he said.
Biden described Republican platforms as threats to American freedom, vowing to fight efforts to limit women's healthcare, cut Social Security and ban books while blasting "MAGA extremists".
MAGA is the acronym for the "Make America Great Again" political slogan of Trump, who may well be Biden's Republican opponent in the November 2024 election.
In a quick reaction, the Republican Party called Biden "out of touch".
"Biden is so out of touch that after creating crisis after crisis, he thinks he deserves another four years," the Republican National Committee said in a statement. "If voters let Biden 'finish the job,' inflation will continue to skyrocket, crime rates will rise, more fentanyl will cross our open borders, children will continue to be left behind, and American families will be worse off."
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Oldest to run for office
In the two years since he took over from Trump, Biden won Congress' approval for billions of dollars in federal funds to tackle the Covid-19 pandemic and for new infrastructure, and oversaw the lowest levels of unemployment since 1969, although a 40-year high in inflation has marred his economic record.
Biden’s age makes his re-election bid a historic and risky gamble for the Democratic Party, which faces a tough election map to hold the Senate in 2024 and is the minority in the House of Representatives now.
Biden’s approval ratings were stuck at just 39 percent in a Reuters/Ipsos poll released on April 19 and there are steep concerns about his age among some Americans; he would be 86 by the end of a prospective second term, almost a decade higher than the average US male's life expectancy.
Doctors declared Biden, who does not drink alcohol and exercises five times a week, "fit for duty" after an examination in February. The White House says his record shows that he is mentally sharp enough for the rigours of the job.
Biden will be joined in his 2024 quest by his running mate, Vice President Kamala Harris.
He ran a mostly virtual campaign to defeat Trump in the 2020 election as covid raged, saying he sought to unify the country, rebuild the economy, and better control the virus.
With pandemic restrictions mostly over in the United States, the 2024 race is likely to be a much different, more physical affair.