District 28 – which stretches from Starr, Webb and eastern Bexar counties - has turned into a political battleground.

It’s represented by Democratic Congressman Henry Cuellar, who has two challengers in his party’s primary election.

Even if he wins, he’ll still have to bear the Republican nominee in November to keep his seat.

“Cuellar faces a very difficult Democratic primary,” Mark Jones, a political science professor with Rice University, said. “It’s quite possible that this gets pushed to a main run-off."

With three Democratic candidates and seven republicans in the primary election, many voters might prefer Cuellar or a Republican over progressive Democrat Jessica Cisneros.

“It reflects a battle that's going on within the Democratic Party between an ascendant left wing and essentially, increasingly marginalized centrist wing,” Jones added.

Jones said even though Cuellar is being investigated by the FBI for his relationship with the country of Azerbaijan, it should not negatively impact his current campaign.

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