Ada Cuellar, a Harlingen-based emergency physician, launched her campaign for Texas’ 15th Congressional District on Thursday, becoming the first Democrat to run for the South Texas seat that her party is targeting in the 2026 midterms.
Anchored in Hidalgo County along the border and running north to the edge of San Antonio, the district — represented by Rep. Monica De La Cruz, R-Edinburg — has been emblematic of Democrats’ recent struggles throughout the Rio Grande Valley and with Latino voters generally. De La Cruz first won office in 2022, becoming the first Republican to represent the district after it was redrawn to favor Republicans.