Mr. Castro divided his remarks into three parts: First, there was the story of growing up the son of a single mom, raised partly by his grandmother Victoria, who had left Mexico when she was a child and worked as a maid most of her life, “barely scraping by, but still working hard to give my mother, her only child, a chance in life so that my mother could give my brother and me an even better one.” Then, he criticized Mr. Romney, delivering the red meat that the party and re-election campaign demanded. (“Mitt Romney, quite simply, doesn’t get it.”) Finally, he told voters why they should choose Mr. Obama.
He’d done several rehearsals on the stage, but 30 seconds after Joaquin introduced him, Mr. Castro clutched the podium, felt the heat of the bright lights and thought he might pass out. (He later confessed that to Mr. Obama, who said that he, too, felt faint before his 2004 keynote.) Mr. Castro got more comfortable as he went on. Watch it on YouTube and you can see his hands unclenching, his expression soften. By the time Mr. Castro concluded, reciting the Spanish words his grandmother had whispered to him — “Que dios te bendiga,” may God bless you — the room roared.
“It didn’t launch him the way it did Barack Obama,” Mr. Messina said. “But he gave a very good speech that was good for us and, for a moment, he was this very big thing nationally.”
Echoes in the 2020 Race
In his 2020 campaign, Mr. Castro has led the party left in the immigration debate. He was the first candidate to propose repealing a section of the immigration laws that criminalizes illegal border crossings. It’s a position that some Republicans believe can be used against the Democrats in a general election where “decriminalization” likely won’t play as well as a proposal framed simply around ending family separations. But almost all of the major Democratic candidates have followed Mr. Castro’s lead on border crossing policy, reflecting both where primary voters stand on the issue and a desire to draw a sharp contrast between the party and President Trump’s views.
“Our current president, for whatever reason, has decided to paint brown people as dangerous and dirty and unwanted, so we need brown people represented,” said Patti Solis Doyle, a Democratic operative and one of Mrs. Clinton’s campaign managers in 2008.
The Castro brothers believe that the current climate makes the echoes of that first major speech and their family’s story even more potent. They dusted off the 2012 keynote address to prepare for the first Democratic primary debate in Miami.
During the debate, as his opponents spoke, Mr. Castro scribbled on a notepad a closing statement that what was essentially a 47-second distillation of his 20-minute convention speech. He repeated the story of his immigrant roots, and he declared that the nation would soon say “adiós” to Mr. Trump. “There is a direct line between what I talked about in 2012 and what I am campaigning on in 2019,” Mr. Castro said.