Elected to the Texas House from District 74 in 1990, Gallego was the first Hispanic to represent this vast border district.
In the Texas House, Gallego served on the board of directors of the National Association of Latino Elected Officials (NALEO), and four terms as Chairman of the Mexican American Legislative Caucus (MALC), a caucus of Texas representatives who are of Mexican-American descent or who serve a significant Mexican-American constituency.