The question, though, is where Julian Castro -- or even his brother -- go from here.
The sky is the limit for young Latino politicians these days -- look at Marco Rubio -- but the Castros face an obstacle in their potential rise: their home state.
While Julian Castro is mayor of one of the largest cities in the country and Joaquin Castro is a state representative and Congressional candidate, there's almost certain to be another step (or two) between where they are now and any national ambitions they might hold. And making the leap to statewide office will be difficult for either, at least right now.
Texas hasn't elected a Democratic governor or senator in more than two decades (the last was Gov. Ann Richards in 1990), and the last Democrats elected lieutenant governor and attorney general came in 1994. The latter two positions are considered the top springboards to either governor or senator.
But things are changing quickly in Texas, with the Latino population accounting for two-thirds of the state's huge growth over the past decade. The state no longer features a white majority, and if the Latino population continues to grow as quickly as it is growing now (and continues to lean heavily Democratic), the state could morph from red to purple.
And what better way for Democrats to rally the Latino vote than to field candidates like the Castros?
Indeed, by 2020, the state could feature more Latino residents than whites, and whites could be less than two-fifths of the population. Whites most likely will still vote in higher numbers, given that many Latinos are young or not registered to vote. But the potential is there for a shift toward a swing state.
Currently, while Democrats can generally win around 45 percent of the vote in Texas, they struggle to get beyond that. In other words, they aren't too far from being competitive. But it is a big state, and getting from 45 percent to 50 percent-plus-one could take some time.
The good news for the not-yet-over-the-hill Castros is they have plenty of time to wait for that to happen. The more Texas trends Democratic and Latino in the coming years, the more opportunities the Castros will have for upward mobility.
For now, though, Julian Castro is playing it appropriately coy.
"I want to be just mayor of San Antonio," he told CNN today.