BuzzFeed reports that Julian Castro, the secretary of Housing and Urban Development and the former mayor of San Antonio, will endorse Hillary Rodham Clinton at an event in the city he led next week.

Castro would join Secretary of Agriculture Tom Vilsack in becoming the second member of President Obama's Cabinet to endorse the former secretary of State.

And as Cabinet members go, Vilsack and Castro bring with them symbolic political value. Vilsack is the former three-term governor of Iowa, the first nominating state, where a strong showing is essential for Clinton.

And Castro is a rising star in the party, who delivered the keynote address at the Democrats' 2012 national convention in Charlotte, N.C.

Of course, any endorsement of Clinton by a member of the Obama administration is significant as Vice President Joe Biden continues to deliberate over his political future .

Castro appeared on the same stage as both Clinton and Obama on Thursday night at the Congressional Hispanic Caucus Institute's annual Award Gala.

Castro's brother, U.S. Rep. Joaquin Castro (D-Texas), will separately headline a kick-off event for Latinos for Hillary in Nevada next week.