Democratic presidential hopeful Julián Castro waves as he arrives for the third Democratic primary debate of the 2020 presidential campaign season at Texas Southern University in Houston. Credit: ROBYN BECK/ AFP / Getty Images

HOUSTON – Sharing the stage with all the Democratic candidates for the first time, Julián Castro sparred with frontrunner Joe Biden in Thursday night’s debate in Houston, strongly criticizing Biden’s health care plan.

In a sharp exchange early in the ABC News-hosted debate featuring 10 candidates on the same stage, the former San Antonio mayor and U.S. Housing and Urban Development secretary accused Biden of flip-flopping and backing a plan that would leave millions uninsured.

“I want every single American family to have a strong Medicare plan available,” Castro said. “If they choose to hold onto strong, solid, private health insurance [they can do that]. … You require them to opt in, and I don’t. They would be automatically enrolled, and that’s a big difference. Barack Obama’s vision was not to leave 10 million uncovered. Your plan would do that. My plan would not.”

When Biden attempted to refute Castro’s statement, Castro spoke loudly over him, in an apparent jab at Biden’s age that drew “oohs” from the audience: “You said two minutes ago they would have to buy in. Are you forgetting what you said just two minutes ago?”

“I’m fulfilling the legacy of Barack Obama and you’re not,” Castro closed.

“That’d be a surprise to him,” Biden retorted.

In the first hour of questions and answers, Castro spoke for less than five minutes but managed to swing at Biden twice. He accused the former vice president of dodging moderator and Univision anchor Jorge Ramos’ question about whether Biden regretted the Obama administration’s high number of deportations.

“My problem with Vice President Biden is every time something good about Barack Obama comes up, he says, ‘Oh, I was there, me too!’ And if someone questions the part of the administration we were both a part of, he says, ‘I was vice president,'” Castro said. “He wants to take credit for Barack Obama and not answer questions.”

Biden said he stood with the former president all eight years of his terms.

“Good, bad, indifferent,” he said. “I did not say I did not stand with him.”

Asked after the debate about his skirmishes with Biden, Castro dismissed assertions that he was questioning the soundness of Biden’s memory.

“This was a disagreement about the best way to do health care,” Castro said. 

But Castro’s attacks on Biden were widely condemned as mean-spirited, and Politifact, an independent organization that fact-checks claims made by politicians and other public figures, rated Castro’s assertions that Biden had switched positions “mostly false.”

Castro, situated on the end of the debate stage Thursday in the auditorium of Texas Southern University, also had an opportunity to weigh in on foreign policy issues. He pledged to press Venezuela and ensure the country holds free and fair elections. He promised to renew focus on Latin America once more, and said President Donald Trump’s trade war with China is hurting Americans. He cited a recently-released poll where 60 percent of Americans said they expect to see a recession within the next year.

“I would immediately begin to negotiate with China to ratchet down that trade war,” he said. “We have leverage there. We have leaders there who are being imprisoned and mistreated. And in North Korea, this president is elevating a dictator. We need to stop that. We need to make sure America leads on human rights.”

Though Castro had a breakout moment in the first round of debates, the energy has not been reflected in subsequent polls. He hovers between 0 and 2 percent in all polls so far. The RealClearPolitics aggregate of all polling data shows his average at 1 percent, putting him behind 10 other candidates, including fellow Texan and former El Paso Congressman Beto O’Rourke. 

Castro told reporters in San Antonio last Thursday that he remains focused on winning.

Univision’s latest poll shows Castro lagging behind the other Democratic presidential candidates among Latinos. Of those polled, 12 percent supported him, while Biden had 22 percent and Vermont Sen. Bernie Sanders had 20 percent. 

Seventy-three percent of Latinos polled said they would vote for the Democratic nominee next year, while 16 percent said they would vote for Trump.

Presidential candidate and former San Antonio Mayor Julián Castro responds to reporters’ questions in the “spin room” following the third Democratic debate.

Castro was the last to answer a question about challenges and resiliency, and he shared how he decided to quit his law firm job while serving on City Council in order to oppose a golf course resort project proposed for the Edwards Aquifer recharge zone.

“It was the first test I had, and I think back on that because often we think on politics as dirty, corrupting,” he said. “I was proud when that first test came, I stood up for the people I was elected to represent.”

He ended his time with a twist on Trump’s slogan: “Together, we can create an America that’s better than ever.”

Castro told reporters later that the key to winning the presidency lies with young supporters, citing the campaigns of John F. Kennedy, Jimmy Carter, Bill Clinton, and Obama as examples.

“That’s the kind of campaign I’m building here – young people who are excited by this campaign, who are taking on issues in a bold, fearless way,” he said. “That’s what’s going to take on momentum and do what Barack Obama was able to do in 2008.”

Castro moves on to Ohio for the next debate in October. The Ohio debate will have at least 11 candidates, as billionaire Tom Steyer qualified for the next round of debates on Sunday.

Jackie Wang covered local government for the San Antonio Report.