TEXAS, USA — While Texas Democrat Julian Castro has already entered the race for president, Beto O’Rourke is still deciding his move for 2020.

But with a crowded race already forming in the Democratic presidential primaries, the two could take a cue from Lyndon Baines Johnson and opt for a two-for-one deal.

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The so-called LBJ Law would allow Castro or O’Rourke to help their chances of elected office by running for one of the state’s two U.S. Senate seats and simultaneously running for president.

The law was passed in 1959 when then-U.S. Senate majority leader LBJ opted to run for re-election to the Senate at the same time he was on the presidential ticket behind John F. Kennedy.

Former U.S. Senator from Texas Lloyd Bentsen then took the same option in 1988, running for U.S. Senate while at the same time running on the national ticket.

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It worked out In LBJ’s case, ultimately carrying him to the vice presidency, and while Bentsen lost the 1988 election to George H.W. Bush, he won the U.S. Senate seat for Texas.

El Paso’s O’Rourke came close to a U.S. Senate win in 2018, and he has indicated he will decide soon whether to run for president.

The LBJ Law is just another option for the Texas Democrats in a year when John Cornyn is up for re-election. It is the only exception to Texas law, which otherwise prevents candidates from filing for more than one office.

Whichever option O’Rourke and Castro choose, it’s sure to be a hard race to the top.