[3] He graduated with a Bachelor of Arts from the University of California, Berkeley, and he received his Juris Doctor from Yale Law School in 1991.

[citation needed] In 1998, Denn was appointed by Governor Tom Carper to serve as chairman of the Child Protection Accountability Commission,[4] formed following the death of a four year old whose abuse and neglect went undetected by a state investigation.

[6] Denn served as Governor Ruth Ann Minner's legal counsel from 2001 through 2003, writing legislation including the Patient's Bill of Rights and the Emergency Health Powers Act.

Denn was elected Lieutenant Governor of Delaware in 2008, winning 61 percent of the vote to defeat Republican opponent State Senator Charlie Copeland.

Another Democratic candidate, Wilmington City Council President Ted Blunt, ended his campaign in spring 2008, allowing Denn to avoid a primary contest.