Congress freshman Joaquin Castro has begun the new phase of his political career with a splash.

With hardly a week on the job, the Texas Democrat has been chosen by his peers to be president of the freshman class of Democrats in the 113th Congress.

The honor comes just months after his twin brother, Julian, made history when he was selected to deliver the keynote address at the Democratic National Convention in Charlotte, N.C. Julian Castro, the mayor of San Antonio, was the first Latino to have such a role in a Democratic National Convention.

Joaquin Castro, who turned 38 in September, was a representative of the 125th district in the Texas House of Representatives. He is one of Congress’s youngest members.

“He’s already out of the crowd,” Texas political consultant Bill Miller told reporters last summer. “He could go far and he could go fast.”

Indeed.

The Mexican-American scion of civil rights activists, Castro is representing the 20th congressional district, which covers a large part of San Antonio, and was represented for nearly four decades by Democrat Charles Gonzalez, who chaired the Congressional Hispanic Caucus.

In November, Castro defeated Republican David Rosa, an insurance salesman. The 20th district is about 64 percent Latino and has a majority –55 percent– of Democrat registered voters. In the House of Representatives, Castro will serve on the House Armed Services Committee. 

The 113th Congress has the most Latinos members in history, with 28 in the House of Representatives and three in the U.S. Senate.

When Joaquin Castro was running to succeed Gonzalez, he told reporters: “I realize I have big shoes to fill. We’ve tried to take nothing for granted.”

As for the twins’ reputation as overachievers, Castro said in an interview with a San Antonio newspaper: “We’ve been very supportive of each other, best friends, since we were young. We were competitive growing up, but as you get older, you mature and mellow a bit.”

In an extensive New York Times Magazine profile on Julian Castro, Mark McKinnon, described as “a member of George W. Bush’s inner circle in Austin,” said: “Julian Castro has a very good chance of becoming the first Hispanic president of the United States.”

Later, Julian Castro was one of Time Magazine’s “40 Under 40,” a list of the country’s most promising leaders. “Higher office may be in Castro's future,” the Time story said.

Castro is the son of an activist named Rosie who was a force in a radical movement in Texas that pushed the case of Chicanos and Mexican American civil rights.

The Castro brothers note that affirmative action helped them get into Stanford, but they note that they did well in school and have done pretty well since. Joaquin graduated with honors there and is also a graduate of Harvard Law School. Shortly after getting his law degree, Julian Castro, at 26, became the youngest elected city councilman at that time in San Antonio history.

Elizabeth Llorente can be reached elizabeth.llorente@foxnewslatino.com

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