Their importance to the Democrats in the November election was apparent.
CHARLOTTE, N.C. - San Antonio Mayor Julian Castro energized the Democratic National Convention on Tuesday night with the story of how his grandmother came from Mexico to build a life in the United States, ultimately leading to his time in the spotlight.
"The American Dream is not a sprint, or even a marathon, but a relay," Castro told the cheering convention delegates.
Castro said his family's personal story highlights the choices Americans face in the election: Americans can choose President Obama's policies that he said invest in future generations or choose his Republican rival's plan that he said helps the wealthy few. And Castro brought the yelling delegates to their feet when he declared: "With the opportunity we build today for a shared prosperity tomorrow, America will prevail."
Democrats were counting on him to excite the party's base and electrify Hispanic voters of all political persuasions who could be decisive in the November election.
Hispanics took center stage on opening night of the Democratic National Convention not only with the first Hispanic to deliver the keynote address but also with the highest number of Hispanic delegates, more than 750, at any presidential convention.
Hispanic voters are being wooed by Democrats and Republicans to a degree never seen before. The fastest-growing voter bloc could be the difference in November, with the election probably decided in battleground states such as Florida and Colorado that have large Hispanic populations.
About 13.6 percent of delegates at the Democratic convention are Hispanics -- nearly three times the estimated 5 percent at the Republican National Conference in Tampa, Fla., last week.
Hispanics also broke records at this year's Democratic convention in terms of leadership posts. Five of the 18 top positions on the convention's standing committees -- such as the platform, rules and credentials panels -- are held by Hispanics.
And the chair of the National Democratic Committee, Florida Rep. Debbie Wasserman Schultz, appointed Hispanics to 19 of the convention's 75 official positions. In past years, that number ranged between zero and seven.
In his speech, Castro stuck to Obama's campaign script focusing on the middle class. He criticized GOP presidential candidate Mitt Romney for failing to understand the challenges most Americans face.
"Republicans tell us that if the most prosperous among us do even better, that somehow the rest of us will too," he said. "Folks ... we've heard that before."
Wasserman Schultz warned people at a Hispanic Caucus meeting this week that a loss for Obama would be devastating for Hispanics who have benefited from his policies, including a new health care law and deferred deportations for young undocumented immigrants. Approximately 32 percent of Hispanics were uninsured in 2009, higher than any other racial or ethnic group, and half of Hispanics did not have a regular doctor, compared with only one-fifth of white Americans, according to the White House.
Wasserman Schultz declared this race "personal for so many Americans, but particularly for Hispanic Americans."
"Julian Castro is one of the key rising stars in our party," she said.
Hearst News Service contributed to this report.