After a surprisingly strong bid for the Democratic nomination in 2016, independent US Senator Bernie Sanders is jumping into the 2020 presidential race for another run
Washington (AFP) - US Senator Bernie Sanders announced another bid for the White House on Tuesday, joining a crowded field of Democrats vying to challenge Republican President Donald Trump in 2020.
The pool of Democratic candidates is among the largest and most diverse ever.
It includes female US senators, African-Americans, Hispanics and a young gay mayor and is likely to grow before the US primary season gets underway a year from now.
Here are the first entrants in the presidential race, 21 months before the election.
- Bernie Sanders -
The 77-year-old Sanders, a self-described Democratic socialist, was an outsider when the 2016 Democratic primaries began.
But he gave favorite Hillary Clinton a run for her money with his calls for a "political revolution" and battled her down to the wire.
Sanders won passionate support among young liberals with his calls for universal health care, a $15 minimum wage and free public university education.
- Amy Klobuchar -
The 58-year-old granddaughter of an iron miner, Klobuchar is a former prosecutor with an unpretentious demeanor.
She has quietly gained attention in Washington as a centrist. Klobuchar is known for putting partisanship aside to pass legislation, something that has earned her a devoted following in Minnesota.
Klobuchar has promised more stringent gun laws and set a target of universal health care.
- Elizabeth Warren -
At 69, the US Senate's consumer protection champion from Massachusetts is on the party's left flank. She built her reputation by holding Wall Street accountable for its missteps. Warren is considered to have one of the best campaign organizations of any Democrat.
Warren's campaign has been dogged, however, by her past claims of Native American heritage and Trump mockingly refers to her as "Pocahontas."
- Cory Booker -
The 49-year-old US senator from New Jersey announced his candidacy February 1, evoking the civil rights movement as he promised to work to bring together a divided America.
Often compared to former president Barack Obama, Booker began his career as a community activist and rose to prominence as mayor of Newark, New Jersey.
A talented orator, he was elected to the US Senate in 2013, the first African-American senator ever from that state.
- Kirsten Gillibrand -
The New York senator made a name fighting sexual abuse, especially in the military, before the #MeToo movement gained national prominence.
The 52-year-old, a fierce Trump critic, is making gender and women's issues a hallmark of her campaign.
- Kamala Harris -
The barrier-breaking senator from California who aspires to be the nation's first black female president announced her candidacy on a day honoring slain civil rights icon Martin Luther King Jr.
The daughter of an Indian immigrant medical researcher mother and a Jamaican economist father, Harris, 54, began her career as a district attorney in San Francisco before serving as California's attorney general.
- Julian Castro -
A cabinet member under Obama and grandson of a Mexican immigrant, Castro announced his candidacy in English and Spanish on January 12 in the heat of the debate on immigration and border security.
At 44, the former mayor of San Antonio, Texas hopes to become the nation's first Hispanic president.
- Tulsi Gabbard -
At just 37, this congresswoman from Hawaii would be the first Hindu president if elected.
A supporter of liberal Bernie Sanders in the 2016 race, military veteran Gabbard was criticized for meeting with Syrian leader Bashar al-Assad during that country's civil war, and for anti-gay positions that she has since retracted and apologized for.
- Pete Buttigieg -
Nine months younger than Gabbard is the South Bend, Indiana, mayor who joined the race unveiling a resolutely future-looking and optimistic message to counter Trump's darker vision.
A Rhodes Scholar, Buttigieg would be the first openly gay nominee of any major party.
A US Navy reserve officer, he put his mayoral duties aside to serve in Afghanistan in 2014.
- Andrew Yang -
The 44-year-old tech entrepreneur launched his campaign with little fanfare in late 2017, warning against the dangers that automation presents to US workers.
He has advocated for a form of universal basic income as a way to reduce inequality.
- John Delaney -
An affluent Maryland businessman who served three terms in Congress, Delaney was the earliest Democrat to officially launch a bid, back in July 2017.
The 55-year-old Delaney has crisscrossed the early-voting state of Iowa seeking to boost his name recognition.
- Waiting in the wings -
Several big Democratic guns have yet to commit, including former vice president Joe Biden and Ohio Senator Sherrod Brown.
Former Texas congressman Beto O'Rourke is also considering a run as is billionaire New York ex-mayor Michael Bloomberg.
Current and former governors are in the mix, too: Washington's Jay Inslee, John Hickenlooper of Colorado, Steve Bullock of Montana and Virginia's Terry McAuliffe.