Kamala Harris has been backed to replace Biden - but who else could challenge her?
US President Joe Biden's sudden announcement that he was dropping out of the presidential race on Sunday immediately raised questions as to who could replace him.
Biden has thrown support behind his Vice President Kamala Harris who, if elected, would become the first black woman and Asian American to lead a major party into a US election.
Despite many Democrats drumming up support for Harris, her path to official nomination may not be smooth, with a chance other potential candidates could throw their hats into the ring.
With the Democratic National Convention in Chicago just weeks away, time is ticking for the party to unite behind a candidate to take on Donald Trump in November's election.
Here are the people that could be battling it out with Kamala Harris for Democrat candidacy.
JB Pritzker
Illinois Governor JB Pritzker is the wealthiest politician holding office in the US, with a net worth of $3.4 billion putting him at No. 250 on the Forbes 400 list of the richest Americans.
The 59-year-old won the nomination for governor in 2018.
Pritzker was praised for his handling of the Covid pandemic, before defeating a Trump-endorsed Republican candidate in the state.
In doing so, he became the first Illinois governor to be elected to a second term in 16 years.
He has noticeably supported national political organisation 'Think Big America', which aims to protect abortion rights.
In October 2022, during an Illinois Governor's Debate, Pritzker said he had no plans to abandon his role as state governor to run for presidency.
Responding to Biden's decision to stand down, he said: "President Joe Biden has dedicated his life in service to this nation, and its citizens are all the better for it."
He vowed to work "every day" to make sure Donald Trump does not win November's election.
Gretchen Whitmer
Gretchen Whitmer became the Governor of Michigan in 2018, after serving for 15 years in the state legislature.
She became more well-known during the final years of Donald Trump's presidency, emerging as one of the Democrat's most effective voices in opposition to him opposing him.
Near the end of 2020, the FBI uncovered a plot to kidnap her, and nine men were convicted by jury or plead guilty for their involvement.
In her 2022 Michigan re-election campaign, she focused her efforts on reproductive rights.
Whitmer has long avoided questions about whether she would consider running for president, telling the Associated Press earlier in July she would not step in as candidate to replace Biden.
But her national profile has been growing, after being considered for the role of Biden's running mate in 2020 and embarking on a national press tour for her new memoir.
Following Biden's departure announcement, she pledged to do "everything I can to elect Democrats and stop Donald Trump".
Pete Buttigieg
Pete Buttigieg, Secretary of Transportation under Biden, was the first openly gay person to be made part of the presidential cabinet.
He was previously mayor of South Bend, Indiana, and served as an intelligence officer in the Navy Reserves. He was deployed to Afghanistan for six months.
Buttigieg also became the first openly gay person to launch a presidential campaign in 2020, before backing down to make way for Joe Biden.
Since Biden announced he was stepping back, Buttigieg has voiced support for Kamala Harris, saying he will do "all that I can" to help elect her.
Gavin Newsom
The California Governor's political career began when he became Mayor of San Francisco in 1997, receiving national attention when he directed the San Francisco clerk to issue marriage licenses to same-sex couples.
Now in his second term as the state's governor, says he is “standing up for California values — from civil rights, to immigration, environmental protection, access to quality schools at all levels, and justice,” according to his official bio.
He has been one of Biden’s staunchest defenders even after fallout from the president’s faltering debate performance.
He appears to have backed Kamala Harris, calling her "tough", "fearless" and "tenacious" in a post on X.
Josh Shapiro
Josh Shapiro is the Governor of Pennsylvania, and has years of experience attacking President Trump, first as state attorney general and now as governor.
In one recent MSNBC appearance, he said Trump should “quit whining” and stop “sh*t talking America.”
If he becomes the official Democrat candidate, Shapiro would become the first presidential nominee of Jewish heritage.
Shapiro has confronted what he viewed as antisemitism from pro-Palestinian demonstrations, and has professed solidarity with Israel in its drive to eliminate Hamas.
He has publicly professed support for the current vice president, and said: I will do everything I can to help elect Kamala Harris as the 47th President of the United States.
Roy Cooper
The North Carolina Governor has won six statewide general elections over two decades.
The 67-year-old has received strong approval ratings as governor, portraying himself as a fighter for public education and abortion rights.
His time as governor also was marked by restricting business and school activity during the COVID-19 pandemic.
He won reelection in 2020 by 4.5 percentage points, even as Donald Trump won the state’s electoral votes.
In a post on X, he expressed public support for Kamala Harris, saying he believes she should be the next president.
Andy Beshear
The Kentucky governor won re-election last year in the traditionally Republican state, focusing on the everyday concerns of Americans, from good-paying jobs to quality education and health care.
Beshear supports abortion rights, and won widespread praise for how he handled the Covid pandemic, and how he led a response to the impact of tornadoes and flooding.
He has presided over record-setting economic growth in the state, and frequently mentions his Christian faith and how it guides his policymaking.
He called for the nation to come together following Biden's announcement that he had stepped down.
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