Cruz or Cornyn vs. Castro or O’Rourke?

The 2018 and 2020 elections got a little more interesting this week when Congressman Beto O'Rourke, D-El Paso, confirmed that he's eyeing a seat in the U.S. Senate. However, O'Rourke left it unclear which incumbent Republican he was thinking about challenging. Sen. Ted Cruz is up for re-election in 2018; the term for John Cornyn, the state's senior senator, ends in 2020. There's also the issue of the other potential name in contention: San Antonio Democratic Congressman Joaquin Castro, who was recently elected chair of the Congressional Hispanic Caucus Institute, and has long been touted as a potential Senate candidate. This week Castro received his first endorsement, from U.S. Rep. Filemon Vela, D-Brownsville. The big wrinkle in all this is that Cruz may not even make it to 2018's general: Repeated speculation has it that the senator could face a serious primary challenge for next March.