• The first 2020 Democratic primary debate featured candidates sharing the stage for the first time.
  • Some candidates managed to break from the pack, but none more than Julián Castro, the former secretary of housing and urban development.
  • Castro in particular engaged former Rep. Beto O’Rourke, a fellow Texan who had a comparatively rough night.
  • Some candidates made waves, while others flailed during their first test on the big stage.
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The first 2020 Democratic primary debate featured lesser-known names managing to break out and showcase big moments, like former Housing and Urban Development Secretary Julián Castro, who engaged other Democrats and issued challenges to the rest of the field.

Castro has rolled out many policy proposals but has so far failed to gain traction in any meaningful polling. But on Wednesday night, Castro became a massive trending topic, producing viral moments and pushing the other nine candidates on key issues.

Read more: Julián Castro is running for president in 2020. Here’s everything we know about the candidate and how he stacks up against the competition.

“I think that you should do your homework on this issue,” Castro said in a skirmish on immigration policy with former Rep. Beto O’Rourke of Texas. “If you did your homework on this issue, you would know we should repeal this section.”

Castro also issued a challenge to the other candidates to pledge to repeal Section 235, which criminalizes unlawful border crossings.

During the debate, interest in Castro skyrocketed as he commanded the stage. According to Google Trends, search interest in the former Obama administration cabinet official exploded 2,400%.

Other candidates managed to hit their marks as well, including Sen. Elizabeth Warren of Massachusetts, whose policy proposals became a focal point of many of the debate moderators' questions, and Sen. Cory Booker of New Jersey, who spoke longer than any of the other candidates during the two-hour debate.

Beto O'Rourke stumbled in his first debate

O'Rourke quickly became a punching bag, taking shots from Castro and Mayor Bill de Blasio of New York.

"Wait, wait, Congressman O'Rourke, private health insurance is not working for tens of millions of Americans when you talk about the co-pays, the deductibles, the premiums, the out-of-pocket costs expenses," de Blasio said, interrupting O'Rourke. "Why are you defending a system that's not working?"

O'Rourke, who entered the 2020 race to much fanfare and a massive fundraising rollout, did not manage to gain back ground during the debate. But O'Rourke did manage to earn a lot of speaking time, coming in just behind Booker.

Read more: Beto O'Rourke is running for president in 2020. Here's everything we know about the candidate and how he stacks up against the competition.

O'Rourke also showcased his fluency in Spanish, repeatedly switching between English and Spanish while answering questions from the moderators. The move, echoed by Booker and Castro, earned some mockery from some of the 2020 presidential candidates scheduled to appear in the next debate Thursday night.

"I need to learn Spanish by tomorrow night at 9," tweeted the self-help guru Marianne Williamson.

The technology entrepreneur Andrew Yang jokingly wrote on Twitter, "My Spanish is terrible."

Whether O'Rourke will suffer as a result of his debate performance is unclear, but Castro is certainly poised to gain some serious traction.