Julián Castro took a victory lap Thursday morning after having his breakout debate performance bolstered by a fundraising boost and a congratulatory text from none other than his primary opponent, Sen. Elizabeth Warren.

The former San Antonio mayor, Obama administration Cabinet secretary and only Latino in the 2020 Democratic field targeted the other Texan in the race, former congressman Beto O’Rourke, over immigration and sought to distinguish himself in a crowded, competitive field.

Castro, who served as Housing and Urban Development secretary for Obama, said the debate yielded his greatest single fundraising haul — “at least in the 2,000 percent range” — since he was among the first to announce his candidacy in January. He began selling T-shirts overnight that say: “Adios, Trump. Castro 2020.”

Democrats discussed transgender issues at the first 2020 presidential debate on June 26, marking a significant moment for the transgender community. (Elyse Samuels/The Washington Post)

“Last night what people saw was that I have a strong vision for the country, that I have the right experience to be president, and they want to know, look, can you stand up to Donald Trump? And I showed that I can more than handle myself,” Castro said during an appearance on MSNBC’s “Morning Joe.” “So I think that people are looking at me in a new way today.”

Castro, who gave a news conference in Miami on Thursday morning, said Warren (D-Mass.) texted him after the debate to congratulate him on “a good job.”

In discussing the emotionally fraught issue of immigration, Castro directly took on O’Rourke by pointing out where they differed on unlawful-entry laws after O’Rourke said asylum seekers would not be turned away in his administration.

At a rally in San Antonio Jan. 12, Democrat Julián Castro said, "There is no way in hell that caging babies is a smart or good" way to secure the border. (Reuters)

But Castro shot back that it was too limited a scope, advocating that the law that criminalizes all illegal border crossings be ended.

“Some of us on this stage have called to end that section, to terminate it. Some, like Congressman O’Rourke, have not,” Castro said. Several other candidates onstage echoed Castro’s call to end that section of immigration law.

Castro acknowledged on MSNBC that he had thought ahead of time about how he differed from O’Rourke — the Texan who has enjoyed more media attention up until this point — but that he was feeling “extra animated” because of the harrowing photo of the migrant father and toddler daughter who drowned crossing the Rio Grande River.

“I was feeling what a lot of people were feeling,” he said, “that we have to make sure that this cruelty from the administration stops, and . . . this is the exact law that has allowed this administration to incarcerate the parents and then separate them from children.”

Castro also said during his news conference that he has a better shot at winning Texas than O’Rourke, and predicted massive Latino voter turnout if he’s the Democratic nominee against Trump.