Michael Edward Cassidy (born September 15, 1955) is a former Democratic member of the Pennsylvania House of Representatives.
Cassidy won his first primary for the 80th district in Blair County, aged 20.
When he was sworn in, he had celebrated his 21st birthday two months earlier, making him eligible to serve in the House according to the Pennsylvania Constitution.
Cassidy is the executive director to the Democratic Human Services Committee under Representative Mark B. Cohen and the managing editor for Commonwealth: A Journal of Political Science.
He is also an adjunct professor through Temple University - Harrisburg.