Rep. Chelsa Wagner was elected to her first term in the Pennsylvania State House in 2006, becoming the first-ever female to be elected for a full term in the State House from the City of Pittsburgh (along with her colleague, Lisa Bennington, who was elected at the same time). Her election to the State House also filled a gender-void in what was the previously all male Allegheny County 23-member delegation. Wagner resides in the Beechview section of the City of Pittsburgh, where she was born and raised. Her uncle, Jack Wagner, is Pennsylvania's Auditor General.

Approximately two-thirds of Wagner’s district is in the City of Pittsburgh, with the other one-third spanning suburban communities to the City’s south. Specifically, the district includes the city communities of Beechview, Brookline, Chateau, Esplen, Manchester, Mt. Washington, Duquesne Heights, Overbrook, Sheraden, Southshore and the suburban communities of Baldwin Township, Castle Shannon and Whitehall.

In the House, Rep. Wagner serves as the secretary/treasurer of the Allegheny County Democratic Delegation. Her committee assignments include Transportation, Judiciary, Education and Commerce. She also concentrates much of her policy work and advocacy in the areas of urban renewal and community development.

Prior to being elected, Wagner worked as a plaintiff's attorney, specializing in medical malpractice with the Pittsburgh firm of Rosen, Louik & Perry. Wagner also worked as a policy analyst reforming large state governments throughout the country. In that capacity, she worked on projects ranging from tax reform to human services in New York City, Virginia and Ohio.

She holds a bachelor’s degree in public policy from the University of Chicago, where she was a member of the women's varsity basketball team, and is a graduate of the University of Pittsburgh Law School, where she was the recipient of the Community Service Award. She is also a graduate of Seton-LaSalle High School.

Wagner serves on the Board of the Pennsylvania League of Young Voters and is the Vice President of the Pennsylvania Young Democrats. She is also a member of the St. Catherine of Siena Parish, a former volunteer for Court Appointed Advocates of Allegheny County (CASA) and former Western PA chairperson of the University of Chicago Alumni Schools Committee.

She enjoys traveling and playing sports, having completed her first marathon, the Marine Corps Marathon in Washington, D.C., in October 2005.