As an attorney, Caballero represented striking farm workers and fought side by side with unions to prevent plant closures. She, along with three partners, founded the law firm Caballero, Matcham & McCarthy, in 1982 to provide low cost legal service. Caballero was recognized with the Athena Award for entrepreneurial excellence.
Caballero served on the Planning Commission and was later elected to the SalinasCity Council in 1991. She was then elected Mayor in 1998. As Mayor, she navigated Salinas through budgetary problems and closed Salinas's libraries as reported by NBC New.[3] Caballero was elected to the State Assembly in 2006.
In 2018, Caballero announced that she would again run for the state Senate to succeed Cannella, who was term limited.[6]
She won the seat, defeating RepublicanMadera CountySupervisor Rob Poythress.
Caballero has also served as the executive director of Partners for Peace, a nonprofit organization dedicated to bringing the community together to prevent gang violence and focus on literacy, early childhood education, and providing services to families. Caballero is also a wife and mother. Her husband, Juan Uranga, is the Director of the Center for Community Advocacy in Salinas.