[5] Nguyen previously served as the executive vice president of the Silicon Valley Organization, now known as the San Jose Chamber of Commerce.

Nguyen began to become more involved in politics in 2001, while working as a sociology instructor at De Anza College;[7] inspired by MTV's "Rock the Vote" campaign, she and members of the Vietnamese community organised a voter drive in which nearly 5,000 new voters registered to vote for the first time.

[3][8] She followed that up with a run for a position on the Franklin-McKinley School District Board of Education, hoping that her election would encourage Vietnamese Americans to get more involved in local politics.

The other, elected around the same time, was Lan Nguyen of Garden Grove, a city in southern California's Orange County.

[4] In September 2005, she ran for city council in a special election to replace Terry Gregory in District 7.

[14] Per Mike Rosenberg of The Mercury News, Nguyen centered her candidacy heavily on her life story, with less emphasis on her record or policy positions.

During her campaign, Rosenberg wrote that Nguyen, "has an inspiring rags-to-riches story stemming from her family’s escape from Vietnam and has built a coalition of supporters — especially the city’s large immigrant population — who see a rare politician they can connect with.

"[15] In April 2015, Madison Nguyen announced her intention to run for California State Assembly District 27, an open seat being vacated by term-limited Nora Campos.

Other declared candidates included San Jose City Councillor Ash Kalra, Santa Clara County Board of Education Trustee Darcie Green, activist Cong Do, and Republican Van Le.

[citation needed] Madison won a decisive victory in the primary, with more than 11,000 more votes than her closest competitor.

Nguyen placed second in the March 2024 primary behind Betty Duong, former chief of staff of supervisor Cindy Chavez[18].