Julian Castro addresses the first session of the Democratic National Convention in Charlotte, North Carolina, US, September 4, 2012. REUTERS/Jessica Rinaldi/Files

WASHINGTON: 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.

"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."

The 45-year-old former mayor of San Antonio, Texas had struggled to raise his profile in a crowded Democratic Party nomination field, rarely rising above two percent in polls.

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