Julian Castro, the former Obama housing secretary and San Antonio mayor, has dropped out of the race for the Democratic presidential nomination.
The only Latino in the field, Castro established himself as one of the more progressive members in the primary race but had been struggling to raise money and fight his way back onto the debate stage.
“It’s with profound gratitude to all of our supporters that I suspend my campaign for president today,” he tweeted. “I’m so proud of everything we’ve accomplished together. I’m going to keep fighting for an America where everyone counts—I hope you’ll join me in that fight.”
In a video released by the campaign, Castro said they've "shaped the conversation on so many important issues in this race, stood up for the most vulnerable people, and given a voice to those who are often forgotten."
Castro started flirting with a White House run in early 2018 with trips to early-voting states and was the first to set up a presidential exploratory committee in December of that year.
But Castro had stalled for most of his campaign around 1 percent in polls and entered October low on money. Castro, 45, was among the youngest in the running but was previously eclipsed by another Texan in the race who dropped out this fall, former Rep. Beto O'Rourke, and another young former mayor, Pete Buttigieg of South Bend, Ind.
His campaign and supporters, meanwhile, grumbled that Castro didn't get due credit for taking out-front positions. For instance, Castro sought to decriminalize border crossings, forcing the rest of the primary field to debate the controversial stance -- most of them ended up endorsing the idea.
Trying to show he could go toe-to-toe with President Trump, Castro swung for big moments on debate stages. But he faced a backlash in September after appearing to swipe at Joe Biden's age by accusing him of forgetting his position on a health care issue.
"I'm fulfilling the legacy of Barack Obama, and you're not," Castro also shot back at the time.
Castro -- who was Obama's housing secretary in his second term -- denied taking a personal dig at Biden as others in the field condemned the exchange.
Castro frequently slammed the Democratic National Committee for their qualifying criteria to make the primary debates. He failed to make the stage in the last two showdowns and was almost certain to be shut out of the January debate as well.
In the autumn he shuttered his small staffs from the early-voting states of New Hampshire and South Carolina in order to focus on Iowa and Nevada, as well as his home state of Texas.
And Castro took aim at both Iowa and New Hampshire -- both overwhelmingly caucasian states -- for traditionally holding the first two contests in the presidential primary and caucus nominating calendar.
In his video announcing he was ending his bid, he emphasized that "it's time for the Democratic party to change the way that we do our presidential nominating process."
Fox News' Tara Prindiville and The Associated Press contributed to this report.