(KCEN) -- There's a new face for San Antonio in the U.S. House of Representatives.
Democrat Joaquin Castro won the race for district 20 over Republican opponent David Rosa.
That's after longtime U.S. Representative Charlie Gonzalez chose not to run for re-election.
Castro is one of several members of the newest freshman class in Washington, D.C.
After his acceptance speech, Castro explained his plans for Bexar County.
He said, "I want to make sure we protect San Antonio in every way. We protect our military bases, we keep growing the economy, we make sure that we get our federal share of research money for our universities, we do everything that we can to build San Antonio up."
Castro's twin brother Julian is the mayor of San Antonio.
He delivered an endorsement speech for President Obama this year during the Democratic National Convention.