WASHINGTON -- With just over 100 days left before U.S. voters cast their ballots in a presidential election, U.S. President Joe Biden dropped his bid for reelection and endorsed Vice President Kamala Harris as the Democratic Party's nominee amid an erosion of support over concerns about his fitness to run because of his age.
Biden had been under pressure for weeks since a horrendous performance at a debate with his rival, Republican candidate Donald Trump.
The 81-year-old appeared frail and confused at times during the June 27 debate, raising questions about his physical and mental state.
The president did not give a reason for withdrawing his candidacy, but he immediately endorsed Harris, to be the party’s candidate, which she vowed to "earn and win" as the August 19-21 Democratic National Convention approaches.
"I have decided not to accept the nomination and to focus all my energies on my duties as president for the remainder of my term," Biden, who is recovering at home in Delaware from COVID-19, said, adding he was acting in the "best interest of my party and the country."
Many Democrats, including former President Bill Clinton, immediately backed Harris to become the Democratic Party's candidate, though it remained unclear whether she would face a challenge to top the election ticket.
The chair of the Democratic National Committee, Jaime Harrison, said the party would comment soon on the path forward for the nomination process after Biden became the first incumbent U.S. president to give up his party's nomination in more than five decades.
"The bottom line is that it's going to be very hard to dislodge her [Harris] from the top spot for all kinds of reasons," Matthew Dallek, historian and political science professor at George Washington University, told RFE/RL.
"She got Biden's endorsement. She can have access to the campaign infrastructure and the campaign dollars. She's been vice president for four years. There's not a whole lot of time. It would be very hard for the Democratic Party, I think, to replace the first African American woman vice president at the top of the ticket with a white man."
Adding to the situation's urgency, Democrats say too much is at stake -- including democracy itself -- to lose the election.
Throughout his nearly decade-long political career, Trump has praised authoritarian leaders like Russian President Vladimir Putin, Turkish President Tayyip Recep Erdogan, and Hungarian Prime Minister Viktor Orban.
During his term in office from 2017 to 2021, Trump tilted the Supreme Court to the right of the political spectrum, sought to overturn the 2020 election results, and -- his critics say -- undermined NATO unity.
Biden beat Trump in 2020, narrowly edging him out in the key swing states of Pennsylvania, Wisconsin, and Michigan.
However, polls showed Trump, 78, expanding his lead over Biden, including in some of those key states, especially after the Republican nominee survived an assassination attempt during a campaign rally on July 13 in Pennsylvania.
"Biden was really fighting two wars at the same time, one against Donald Trump and the Republican Party, and then one against his own party, the Democrats. I think that that was just too much to keep an election campaign going heading into a general election," Thomas Gift, associate professor of political science at University College London, told RFE/RL.
Republican leaders immediately attacked Harris over the Biden administration's policies, with some saying that if Biden was not fit enough to run for president, he should step down from the position, a move analysts said was unlikely to happen.
"There's been a lot of evidence, I think, that Biden is really diminished as a campaigner. But in terms of his ability to govern and to make decisions, and to make informed decisions, I don't think we've seen that," Dallek said.
If chosen as the Democratic candidate, Harris, a 59-year-old former prosecutor and California senator, would become the first black woman to run at the top of the election ticket for a major party in the country's history.
Harris oversaw several key issues in the administration, including immigration, voting rights, and reproductive rights. She also strengthened her international profile during her three years in office, making more than a dozen trips abroad and meeting about 150 leaders.
Harris also represented the United States at Ukraine's peace summit in Switzerland last month.
Other names commonly floated as potential contenders for the Democratic nomination have included governors Gavin Newsom of California, Gretchen Whitmer of Michigan, Josh Shapiro of Pennsylvania, and J.B. Pritzker of Illinois.
Harris shares a similar disapproval rating as Biden. However, experts say she is still not well-known to many Americans and can improve her image as she campaigns around the country.
Biden's backing of Harris gives her a clear path to the nomination, likely avoiding an intraparty brawl, Gift says.
"These last few weeks have been bad enough for Democrats. The last thing they needed was a really bruising convention. So I think that it made sense for Biden to go ahead and endorse Harris," he said.
Democrats also risk alienating black voters, a key part of their base, if they pass up on Harris, analysts say.
"He has done one of the most difficult things for any political leader, and has done so in the national interest," presidential historian Michael Beschloss said in a post on X.
Biden's announcement means his political career of more than half a century will finally come to an end in January 2025 when his successor is inaugurated.
In 1972, at the age of 29, Biden won the Delaware Senate race. He held that seat for the next 36 years, serving as chairman of the powerful Senate Foreign Relations Committee. He ran for the Democratic nomination in 1988 and 2008, losing both times.
Obama, considered a novice in foreign affairs, tapped Biden to be his running mate in 2008. Biden served as vice president for the next eight years, overseeing White House policy on Ukraine and making several trips to Kyiv.
In Photos: The Life Of Kamala Harris
Like most vice presidents, Biden wanted to run for the nation's top office in 2016 but was encouraged to make way for former U.S. Secretary of State Hillary Clinton, something he is reportedly still bitter about. She was beaten by Trump in one of the biggest upsets in presidential history.
In his third bid for the presidency in 2020, Biden beat incumbent Trump in a close race, becoming the oldest person to hold the top office. He immediately sought to rebuild relations with European allies damaged under his predecessor.
With Biden bowing out before officially becoming his party's nominee, Trump, 78, is now officially the oldest presidential nominee in U.S. history.
In what is likely to be one of his enduring legacies as president, he was able to quickly unite those allies to support Ukraine with tens of billions of dollars in military and financial aid when Russia launched its full-scale invasion in February 2022.
