San Antonio Mayor Juliàn Castro took center stage at the 2012 Democratic National Convention as he delivered a rousing speech. 

"My fellow Democrats, my fellow Texans, my fellow Americans: I stand before you tonight as a young American, a proud American, of a generation born as the Cold War receded, shaped by the tragedy of 9/11, connected by the digital revolution and determined to re-elect the man who will make the 21st century another American century-President Barack Obama," Castro said to a round of applause.

Castro is the youngest mayor of a major U.S. city and made history as the first Hispanic to deliver a keynote address at the Democratic National Convention -- a role that propelled the 37-year-old from political obscurity to national prominence.

As Castro tried to inspire independents and his party, he did not spare the Romney-Ryan ticket, telling millions that Mitt Romney "simply doesn't get it."

"We know that in our free market economy some will prosper more than others," Castro said. "What we don't accept is the idea that some folks won't even get a chance. And the thing is, Mitt Romney and the Republican Party are perfectly comfortable with that America. In fact, that's exactly what they're promising us."

Throughout most of his speech, Castro talked about the middle class and the American dream. 

"The Romney-Ryan budget doesn't just cut public education, cut Medicare, cut transportation and cut job training," he Castro said. "It doesn't just pummel the middle class-it dismantles it. It dismantles what generations before have built to ensure that everybody can enter and stay in the middle class."

Castro said the middle class is the engine of America's economic growth. He also spoke about the American dream, calling it a human dream that "calls across oceans and borders."

"The dream is universal, but America makes it possible," Castro said. "And our investment in opportunity makes it a reality."

Castro spoke about his American dream and how it became a reality. He told stories about living with his mother and grandmother. Castro said his grandmother was an orphan who left home in Mexico to move to San Antonio.

"She never made it past the fourth grade," Castro said. "She had to drop out and start working to help her family. My grandmother spent her whole life working as a maid, a cook and a babysitter, 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."

Castro also used the opportunity to defend President Obama's record, that was attacked at last week's Republican National Convention. 

"When Detroit was in trouble, President Obama saved the auto industry and saved a million jobs," Castro declared. "Seven presidents before him-Democrats and Republicans-tried to expand health care to all Americans. President Obama got it done. He made a historic investment to lift our nation's public schools and expanded Pell grants so that more young people can afford college. And because he knows that we don't have an ounce of talent to waste, the president took action to lift the shadow of deportation from a generation of young, law-abiding immigrants called dreamers."