Editor's note: This story has been updated throughout.
Despite growing speculation that he could be tapped to serve as the running mate of Democratic presidential frontrunner Hillary Clinton, Julián Castro said Sunday “it's not a given” that he’d accept the position.
In a wide-ranging interview at the Texas Tribune Festival, Castro, the U.S. secretary for housing and urban development, brushed off the possibility that he’d be considered for the job of vice president. Castro endorsed Clinton on Thursday.
“I don’t fundamentally believe that I will be selected,” Castro told Tribune CEO and Editor-in-Chief Evan Smith before adding he was unsure whether he’d accept. “If I had that opportunity presented then of course, like anyone else, my family and I would have to give that very serious thought.”
Since being tapped to lead the housing department, Castro, a former mayor of San Antonio, has been mentioned as a possible running mate for Clinton. During a campaign stop in his hometown on Thursday, Clinton addressed those rumors, saying she plans to “really look hard at him for anything.”
"That's how good he is," Clinton added in a Q&A with Javier Palomarez, the head of the U.S. Hispanic Chamber of Commerce.
Republicans, who are already treating Castro like Clinton’s running mate, have accused Castro of being more interested in building a brand than running the housing department.
On Sunday, Castro said he disagreed with Clinton on some issues, including her opposition to the far-reaching Trans-Pacific Partnership trade deal. Clinton has said she does not support the deal while Castro said he supports President Obama's efforts to work the deal through Congress.
But Castro reiterated that he endorsed Clinton because she's a "progressive" who can beat anyone in the crowded GOP presidential field.
(Shortly after the interview, America Rising, a conservative political action committee, pounced on Castro’s comments on the trade deal, saying Castro had "created trouble for himself not only in 2016 but with key Democrat constituencies.")
Asked about a possible presidential run by Vice President Joe Biden, Castro said Biden would do a “phenomenal job” but declined to speculate about the viability of his campaign. As for U.S. Sen. Bernie Sanders, I-Vermont, Castro said Clinton’s top rival for the Democratic nomination could be elected president but that “it would be more difficult” for him to secure the White House.
During the interview, Castro avoided providing specifics on his political future beyond his role in the Obama administration. But he dispelled any rumors that he may be challenging Republican Gov. Greg Abbott in 2018, calling a possible gubernatorial candidacy “extremely unlikely.”
“Would I say there is zero chance? I wouldn’t say that either,” Castro said. But he added that other Texas Democrats, particularly state Sen. Kirk Watson, D-Austin, and state Rep. Trey Martinez Fischer, D-San Antonio, would be good candidates for the job.