Castro is a golden boy of the San Antonio political scene, alongside his brother, Mayor Julián Castro. The two have been heralded as the new face of Democratic politics after they were honored guests at the Democratic National Convention.
Though their mother was a Mexican-American political activist, the Castro brothers did not become interested in politics until college. They both returned home from school and ran for office, Julián for city council and, two years later, Joaquin for the Texas Legislature.
He says he wants to provide other children with the same opportunities he had, perhaps from a perch on the Education and the Workforce Committee.
"My top priority in the Texas Legislature has been getting more students to college and getting them to graduate," he says. "For me and my family, education was the path to success. I think for all Americans, education is the surest path to success."
Representing a heavily Latino district that comprises most of the inner city, Castro wants to grow the district economically, address the citys infrastructure needs and help several nearby military bases.
"I feel the responsibly of being the main San Antonio representative," he says.
That may lead him to seek a spot on the Energy and Commerce Committee. But a panel dealing with the military would also suit him well, he adds.
Castro says he will also be joining the Congressional Hispanic Caucus and the New Democrat Coalition.
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Vice President Joe Biden waits to conduct a mock swearing-in ceremony with Sen. Brian Schatz, D-Hawaii, in the Capitol's Old Senate Chamber, December 2, 2014. Schatz was sworn in to serve the remainder of his term since he was appointed to the seat after Sen. Daniel Inouye, D-Hawaii, passed away.