(CNN) It's the old guard versus the new.

Human rights and immigration attorney Jessica Cisneros, 26, once worked as an intern for Democratic Texas Rep. Henry Cuellar's office.

Now, she's running against her former boss, seeking to unseat him in the state's 28th District.

As an intern for Cuellar in 2014, she mainly handled constituent relations and press inquiries, her campaign told CNN.

Cisneros has accused Cuellar of representing Trump interests rather than his district, which Hillary Clinton carried by nearly 20 points in 2016.

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