After serving Louisiana's sixth district in the United States House of Representatives, this Republican Party politician became a United States Senator.
He received both his bachelor's degree and his M.D. from Louisiana State University and became a liver specialist at the Earl K. Long Medical Center in Baton Rouge. In 2006, he entered politics as a Louisiana State Senator.
He helped organize healthcare for schoolchildren in East Baton Rouge Parish and also operated a makeshift emergency clinic in the days following Hurricane Katrina.
Born to James and Elizabeth Cassidy in Highland Park, Illinois, he later relocated to Louisiana, where he married physician Laura Layden and fathered a son named Will and daughters named Meg and Kate.
Before becoming affiliated with the Republican Party, he supported the 1988 presidential campaign of Democratic candidate Michael Dukakis.