Before coming to the Assembly, Blanca served two terms as the Mayor of Downey, the largest city in her district, becoming the first Latina to be elected to that position. She was elected to the Downey City Council in 2016 and became Mayor in 2020. Blanca also served as President of the League of California Cities Los Angeles Division, where she chaired the Housing, Community, and Economic Development Policy Committee and was an at-large director on the League of California Cities' State Board.

Blanca is a proud alumna of UCLA, receiving her bachelor's degree in political science with a specialization in Chicano/a studies in 1998. She furthered her education at Loyola Law School and has been an attorney since 2003. The daughter of a nurse and a public school bus driver in a working-class neighborhood, Blanca's upbringing instilled in her an appreciation for hard work and the importance of community.

In and out of the legislature, Blanca is known for her warm, approachable demeanour. But don't let that fool you, she is a frequent boxer and holds a black belt in karate.