Julian Castro, the little-known mayor of San Antonio, Texas, will be the keynote speaker at the Democratic National Convention in September, party officials announced this week. Castro, 37, is the first Latino chosen for the honor, "a clear sign of the importance of the Hispanic vote to President Obama's re-election math in November," says Sean Sullivan at The Washington Post. Considered a rising Dem star, Castro resembles in many ways another once-obscure politician who gained national prominence by giving the DNC keynote address in 2004: Then-Senate candidate Barack Obama. Castro has even been dubbed the "post-Hispanic Hispanic politician," a nod to the post-racial model Obama has cultivated. Here, a guide:

Who exactly is Julian Castro?

A native of San Antonio, Castro grew up in a political family. In the 1970s, his mother, Rosie Castro, was a leader of Texas' Chicano political movement, which sought equal rights for Latinos. Castro's twin brother, Joaquin, is a state representative in Texas. Castro earned an undergraduate degree from Stanford, and, like Obama, attended Harvard Law School. Upon returning to Texas, he was elected mayor of San Antonio in 2009, at just 34. He was re-elected in 2011 with 82 percent of the vote.

What's he like?

"He is cerebral, serious, self-contained, and highly efficient," says Zev Chafets at The New York Times. "If he were an energy source, he'd be zero-emission." John Podesta, a longtime Democratic operative, says Castro is a "super smart, effective, innovative leader," and "young and Latino" to boot. "What's not to love?"

Is Castro a liberal Democrat?

In some ways, yes. He's a big believer in affirmative action, and has admitted that his SAT scores were not good enough to get him into Stanford on their own. "But I did fine in college and in law school," he tells Chafets. "I'm a strong supporter of affirmative action because I've seen it work in my life." However, he's a moderate on many issues: He supports the North American Free Trade Agreement, which has been opposed by unions, and his preferred energy policy includes a hearty dose of fossil fuels. He says his ideal Supreme Court justice is David Souter, a moderate who was appointed to the bench by George H.W. Bush.

How is he a "post-Hispanic Hispanic"?

Like Obama, Castro belongs to a generation that benefited enormously from the civil rights movement, but whose politics aren't entirely defined by it. Compare his mother, Rosie Castro, who says she views the Alamo, where a ragged band of Texans held off a Mexican army, as a symbol of white imperialism. "I can truly say that I hate that place and everything it stands for," she tells Chafets. Her son, meanwhile, steers clear of the kind of identity politics that can alienate non-Latinos. "I don't want to turn my back on my mother's generation," he says. "But we are less burdened." Castro isn't even fluent in Spanish, choosing to study Japanese and Latin in college instead.

Does he know Obama?

Yes. When Obama first met Castro at a White House forum on economic growth, he ribbed him for looking so young, saying, "I thought he was an intern." Castro, in announcing his upcoming keynote address, in which he's expected to vigorously defend Obama's record, explicitly referenced Obama's 2004 speech: "When Obama talked about the audacity of hope, I thought back to my mother saying if you didn't like the way things were, you could dare to change them. I thought, my mother would like this guy."

Could Castro eventually be the first Latino president?

Maybe. At the least, he's considered a top candidate to become the Latino community's most recognizable Democratic politician. Some serious obstacles, however, could block his path to the national stage. He could face difficulties winning Texas' governorship, the surest stepping stone to the White House, in a state as red as states get. If he did become governor, says Joaquin Castro, he'd be golden: Any "Democrat who can win the governorship of Texas would automatically be under consideration for a spot on the national ticket."

Sources: The Daily Beast, Daily News, Fox News, The New York Times (2), NPR, The Washington Post

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