In 2018, she finished in second place over Baldwin Park City Councilwoman Monica Garcia in the primary, then won November runoff against former state Assemblyman Mike Eng.

Her district comprises the cities of Alhambra, Arcadia, Azusa, Baldwin Park, Covina, El Monte, Industry, Irwindale, La Puente, Monterey Park, San Gabriel, Rosemead, South El Monte, Temple City and West Covina as well as the unincorporated communities of Avocado Heights, Charter Oak, Citrus, East Pasadena, East San Gabriel, Mayflower Village, North El Monte, South Monrovia Island, South San Gabriel, South San Jose Hills, Valinda, Vincent and West Puente Valley.

[6] She is also a Select Committee member of The Social Determinants of Children’s Well-Being; Asian Pacific Islander Affairs; Mental Health; California-Mexico Cooperation; and California, Armenia and Artsakh Mutual Trade, Art and Cultural Exchange.

She also passed SB 316, which requires the number of the National Domestic Violence Hotline to be printed on the back of student ID cards.

[9][10] In December 2024, a plea agreement was unsealed which revealed that somebody fitting Rubio's description was part of a cannabis-involved corruption investigation in 2018.

[14] Her ex-husband is former Assemblyman Roger Hernández, whom she divorced in 2016 after winning a restraining order due to allegations of several domestic violence incidents during their marriage, including "pushing, shoving, and choking" her.