Over breakfast recently, San Antonio mayor Julián Castro, only 35 years old, struggled to place himself and his generation in the long, storied history of Mexican American politics in Texas. “I’m kidded a lot about being young, but youth has its advantages,” said Castro, leaning across the table as if into a stiff wind. “I didn’t experience discrimination growing up. I’ve been able to get a good education and my dream job. A lot of things define me: the fact that I’m married and have a young daughter, that I’m a lawyer. I’m Latino, but that’s not the only factor that shapes my thinking. It’s only part of my identity.”

We were at Jim’s coffee shop on Broadway, just north of downtown. Every few minutes, customers would come over to greet the mayor. And each time, Castro would lift his lean, five-foot-eight-inch frame from his seat and offer his thanks with the air of an enthusiastic priest. At one point, a gray-haired Hispanic woman approached, stared into Castro’s face, and pressed a Catholic prayer card into his hand. “I am so proud of you,” she said. “I want you to remember that I pray for you every day.”

In thirty years of writing about San Antonio, I’ve witnessed this small scene play out many times before with previous generations of Hispanic hero politicians, who, like Castro, grew up on the predominantly Hispanic West Side. In the late seventies, when Congressman Henry B. Gonzalez would go to breakfast, he’d bring his own fresh peppers, dice them with a knife at the table, and mix them into his scrambled eggs. He’d give customers the Henry B. treatment, handing out ballpoint pens with his name on them and calendars with his photo. They wound up in Hispanic homes and offices all over town, totems of reverence. After Henry Cisneros was elected mayor, in 1981, he too had breakfast with reporters on Broadway. Cisneros would walk table to table, his suit jacket slung over his shoulder JFK-style, shaking hands, always in motion and oozing charisma.

Both men transcended longtime ethnic politics in ways that provide useful lessons for Castro. The son of immigrants, Henry B. did not speak English when he started school, but he would later become known for his ability to make inspiring speeches. He saw himself as a Hispanic politician, one who represented San Antonio but also national interests in Congress. At home, however, no one disputed that he was el jefe, a figure feared as much as admired. When Henry C. became mayor, winning 61 percent of the vote, he was so cautious about offending Henry B. that he promised never to run against him. During his four terms, he presided over an economic boom and was as popular with Anglos as he was with Hispanics. Privately, however, he agonized over the pressures of ethnic tensions. While others saw him as a future governor or U.S. senator, Henry C. cheated his own destiny with his paralyzing indecisiveness about his future and, later, with a messy public admission of an extramarital affair.

These days Cisneros, who is the executive chairman of CityView, an institutional investment firm that focuses on housing for working families and urban infrastructure, plays the offstage role of adviser. Castro and his twin brother, Joaquin, a state representative, sometimes meet with Cisneros on Saturday mornings at spots like El Mirador and El Sol Bakery for tutorials. Cisneros went to kindergarten with Rosie Castro, the twins’ mother, and has known them since they were children. “I want to help Julián and Joaquin and the next generation all I can,” said Cisneros during an interview in his downtown office. “In particular, I want for Julián what I want for my own son—to go as far as he can.”

Castro is a graduate of Stanford University and Harvard Law School, and he believes that his ideas, not his ethnicity, will define his political future. Both Henrys thought the power of their ideas would elevate them as well. The difference is that Castro has demographics on his side. Within fifteen years, Hispanics, already the largest ethnic group in Texas, will become a majority. Yet the political shift from Anglos to Hispanics will not be quick or easy. Voter turnout among Hispanics has been historically low and has risen by inches, not feet. During the 2008 presidential election, about 10.2 million Hispanics voted, up from 9.6 million in 2004. Sixty-seven percent voted for Barack Obama, helping push him over the top.

In the future, some smart, engaging Hispanic Democrat like Castro could be elected governor of Texas. The Los Angeles Times and the Economist have written stories that have prominently mentioned Castro as a future leader of the coming Hispanic majority. He’s appeared on Fox, MSNBC, and ABC, where on Good Morning America Diane Sawyer mispronounced his name, calling him “Joo-lee-un” instead of “Hoo-lee-ahn.” In December Castro traveled to the White House for a jobs summit with business leaders and Cabinet officials. An hour or so into the meeting, President Obama entered the room.

“I thought you were on staff, maybe an intern,” said Obama, ribbing Castro. “Are you really a mayor?”

“San Antonio, Texas,” Castro shot back, taking no guff.

“Just kidding,” said Obama, who knows a thing or two about what it’s like to be representative of demographic change. “I know exactly who you are.”

In late January, eight months after he was elected mayor, Castro stood at the lectern in a ballroom of the Grand Hyatt Hotel packed with nine hundred business and community leaders, a chamber of commerce crowd of mostly Anglos and many Republicans. “I believe that 2010 marks the beginning of the decade of San Antonio,” said Castro. “This is the decade that we will emerge as an economic powerhouse across the nation and across the world.”

Over the clatter of cutlery, Castro laid out his audacious vision for his administration: to create 20,000 new jobs in 2010, go to war against the city’s 50 percent high school dropout rate, build a new streetcar system, invest in renewable sources of energy, rebuild downtown, and forge relationships beyond our borders with, of all places, Shanghai. San Antonio has long envisioned itself as sleepy and insular, slightly removed from the center of action, so Castro’s hip, urban, and expansive style represents, well, something new. Yet the audience nodded its approval. This too was new. When Castro ran for mayor five years ago, he lost because San Antonio’s moneyed players thought he was too young, too ambitious, and too loyal to his activist Hispanic roots. As an inner-city council member from 2001 to 2005, Castro opposed a PGA-approved golf course and large-scale real estate development on the city’s outer rim, which aroused suspicion. But as mayor, Castro’s businesslike approach and his focus on creating jobs have won many over.

His manner is not hypercharged in the usual style of the braggadocio Texas politician. Instead, Castro is never less than respectful, often reserved and always deliberative. He pauses a lot and sometimes sighs. His dress is business-appropriate: dark suits; black, well-shined shoes; white shirts; and a preference for pale ties, like the off-white one he wore for this particular speech. “He doesn’t show his hand,” said Jim Dublin, a public relations adviser for many top executives in San Antonio. “But the business community likes the way he’s handling himself so far. We’re pulling for him.”

Still, Castro’s ability to deliver on his outsized vision for San Antonio is questionable. He came into office in the middle of a recession, faced an $11 million deficit in the city budget, and inherited a mismanaged plan for San Antonio to invest in a proposed expansion of a nuclear power station, the South Texas Project, in Bay City. To deal with these pitfalls, Castro successfully made collaboration part of his playbook, which kept the controversies from flaring and collapsing along the old ethnic patterns of Anglos versus Hispanics. San Antonio has a council-manager system of government, and Castro worked closely with the city manager to solve the budget crisis. Cuts were made quickly and quietly without drama.

Regarding the South Texas Project, he carved out a clear, centrist position. He said he supported it as long as the numbers made sense, and he patiently stuck to it. Most business leaders supported his pragmatic stance. But when Castro learned that CPS Energy, the city’s utility, had concealed a $4 billion cost overrun, he went public, making transparency another part of his playbook. He forced the resignation of high-level staff and the chairman of the CPS board. He also initiated the filing of a lawsuit against the city’s managing partner, NRG Energy, which owned a 50 percent stake in the nuclear project. In the end, the parties reached an out-of-court settlement that reduced San Antonio’s share to a little more than 7 percent. Castro’s approach to the nuclear issue was firm but not antagonistic. Unlike Cisneros, who played offense, Castro let the fight come to him while building alliances across Hispanic and Anglo lines. In the end, he forged consensus.

It’s not likely, however, that he can deliver on 20,000 new jobs; to do so would require Castro to defy all economic trends. In 2009 San Antonio lost 10,000, more than 500 of them when AT&T moved its corporate headquarters to Dallas. On the other hand, the city has actually benefited from Toyota’s recent economic troubles. The company decided to shift production of the Tacoma, a compact pickup, from California to its plant on the South Side, which means more positions.

As for tackling the high school dropout rate, Castro has little official power as mayor to effect change, other than persuasion and his own motivational story. He has started a mentoring program, pairing at-risk eighth-graders from the inner city with lawyers, engineers, and other professionals. He has created a center on the edge of downtown where students can apply for college and apply for student loans. And he’s made it a priority to visit every middle school in Bexar County. His message is always the same: “My brother and I were just like you, poor kids raised by a single mother. We went to inner-city public schools, and we weren’t that special. But we worked hard. If we can do it, you can too.” His commitment to education might sell better statewide among Democrats, but to move the needle on such an entrenched social problem locally seems unlikely. Another big-city mayor, Los Angeles’s Antonio Villaraigosa, made dropout rates a priority early in his administration, without much success.

Late one Friday afternoon, Castro slipped behind the wheel of his midnight-blue 2007 Lexus sedan and pulled out of his parking space at city hall. He was taking me on a tour of the West Side. As we drove away from the center of the city over the West Commerce Street Bridge, we headed into the close-knit neighborhood of small bungalows and businesses. I asked if he felt the kind of pressure to mediate ethnic tension that Cisneros had nearly thirty years ago. “No, I really don’t,” he said. “Part of it may be that now there is a larger number of bridge builders, both Anglo and Hispanic, than when Henry was mayor. I’m not trying to do this all by myself.”

We drove deeper into the West Side and parked in front of 814 Plainview, a small wooden house. In September 1974, after Julián and Joaquin were born, Rosie, a Chicana activist and former chair of the Bexar County La Raza Unida party, and their father, Jesse Guzman, a schoolteacher in the Edgewood district, brought the twins to this rented house. Unlike Cisneros or Gonzalez, the Castro twins grew up in a poorer, less stable family. Their parents never married. When the boys were seven, their father left. Rosie, who’d run for city council and lost three years earlier, worked in the city’s personnel department. Some mothers have the ability to impart their personal values and ambition to their children without crippling them with expectations. Rosie is one of them. On the day that Castro moved into the mayor’s office, he carried only two items. One was a campaign poster from Rosie’s 1971 race for the city council, a symbol of who brought him to the table of power. The other was a dock for his iPod.

This particular moment the song playing on the iPod was “Take It Easy,” by the Eagles. We rode along in silence during the chorus: “Take it easy, take it easy, don’t let the sound of your own wheels drive you crazy.” I remembered what Castro said about not feeling much pressure, and the placid look on his face, combined with the sunny lyrics of the song, convinced me it was true.

He’s taken the path that worked for Cisneros—his Ivy League education that transcended the West Side, his message of economic development, and his furious pursuit of ideas that will solve every major problem facing San Antonio. He should learn as well from Cisneros’s mistakes. Castro seems to understand that in today’s partisan climate, the most effective way to amass power may be to avoid being seen as powerful at all.

Castro knows that his future depends on his success in San Antonio. The climb from council member to mayor to governor is a steep one. But if Castro delivers as mayor, he might have a shot at running for governor in 2014, should Republican incumbent Rick Perry win this fall, or in 2018, if Democrat and former Houston mayor Bill White does. “I’m not a flash in the pan,” said Castro. “I’m going to be around a long time.”

Toward dusk, we pulled up to a small red-brick house on a lot filled with trees at 715 Sunshine. This is where Castro lives with his wife, Erica, a pretty brunette who works for the school district, and their daughter, Carina, who was born less than two months before Castro was elected mayor. The house is decorated in earthy colors of crimson and beige and has plushy sofas and a large-screen TV. Castro headed straight for the kitchen, where Carina squirmed in a high chair. At city hall, Castro chooses his words carefully, does not express emotion, and does not show his hand quickly. Here he instantly relaxed. As he offered his daughter Cheerios—one round piece at a time—he laughed easily. Whether with Castro or someone else, the future of Texas will one day be in the hands of someone who speaks English and Spanish—with a dash of Big Spring or Lufkin thrown in (a talent Castro does not yet have). Nonetheless, in that moment with his daughter, the wonder of possibility and the weight of obligations seemed stunningly present. In the face of it, Castro took it easy.