Julian Castro, only Latino, drops out of US Prez race

Julian Castro, an Obama-era cabinet member and the only Hispanic candidate in the US presidential race, ended his 2020 White House bid Thursday after failing to boost his flagging poll numbers in a crowded Democratic field.

The 45-year-old former housing secretary and mayor of San Antonio, Texas rarely rose above two per cent support.

His exit leaves 14 candidates, most of whom are white and older, in the battle to win the right to challenge Republican President Donald Trump in November.

"It's with profound gratitude to all of our supporters that I suspend my campaign for president today," Castro said on Twitter, adding that he would "keep fighting for an America where everyone counts."

His tweet featured a three-minute video montage of clips from his campaign trail.

The video, which focuses on Castro's work on immigration reform and race issues, appears to express frustration at the dwindling diversity in the Democratic field.

Castro attempted to make a splash during the September debate by going after frontrunner Joe Biden, accusing the former vice president of "forgetting what you said just two minutes ago."

But the comment -- seen as a below-the-belt attack -- drew boos, and his campaign ultimately flatlined.

Castro and Senator Kamala Harris are two of the biggest names to drop out of the Democratic race, along with former congressman Beto O'Rourke of Texas and New York Mayor Bill de Blasio.

Biden, Bernie Sanders and Elizabeth Warren are the frontrunners for the nomination.

After announcing his departure, Castro quickly received accolades from fellow candidates.

"Your voice and campaign were invaluable in sticking up for underrepresented communities and pushing the field forward," wrote Senator Cory Booker, the sole black candidate left in the race.

Entrepreneur Andrew Yang congratulated Castro for his campaign that "elevated the right issues."

"Too many Americans feel left out and left behind. I know you will continue to fight for them," said Yang.

Neither Yang nor Booker has qualified for the January debate, and Yang was the sole candidate of colour on stage during the December debate.