AUSTIN, Texas — Anticipation of a 2020 Texas ballot featuring the Castro twins fizzled Wednesday when Rep. Joaquín Castro decided against running for the Senate.

Castro announced to Hearst Newspapers that he will not challenge the state's senior senator, John Cornyn, a Republican in his third term. Castro said that if he did run again it would be for something that takes him back to Texas.

“Right now, I’m going to focus on my work in the House of Representatives. I’ve been doing what I feel is important and meaningful work here,” Castro told The Express-News.

Castro is the twin brother of Julián Castro, who is seeking the Democratic 2020 presidential nomination, and Joaquín is his brother's campaign chairman. Julián Castro had predicted a more compelling election in Texas and a swell of interest in the primary if he and his brother were both on the ballot.

Joaquín Castro is a member of the House Intelligence Committee, one of the key committees investigating Russian influence in the 2016 election and the Trump 2016 campaign and administration.

He also is chairman of the Congressional Hispanic Caucus and has been outspoken on President Donald Trump’s immigration policies. He was the lead sponsor on a legislative measure to rescind Trump’s declaration of a national emergency at the border.

According to The Texas Tribune, several reporters on Cornyn's weekly conference call Wednesday learned of Castro's decision when one reporter on a call with Castro forgot to mute his phone and the reporters could hear Castro say that he was going to pass on challenging Cornyn.

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