Denman was born and raised in Buffalo, New York and graduated from the University of Buffalo as a Musical Theatre Dance major.
He made his Broadway debut in the 1995 revival of How to Succeed in Business Without Really Trying, played Munkustrap in the closing company of Cats and understudied Matthew Broderick in the original cast of The Producers. He was the assistant choreographer and understudy for the Noël Coward role in the Off-Broadway musical revue If Love Were All in 1999.
At New York City Center Encores! concert series he played Jenkins in Of Thee I Sing (2006) and Pat Mason, Jr. in Face the Music (2007).
In 2004 he originated the role of Phil Davis opposite Brian d'Arcy James, Anastasia Barzee and Meredith Patterson in the World Premiere production of Irving Berlin's White Christmas at the Curran Theatre in San Francisco. In 2008 he starred in the original Broadway production opposite Stephen Bogardus, Kerry O'Malley and Meredith Patterson.
He co-starred in Ken Ludwig's musical The Gershwins' An American in Paris at the Alley Theatre, Houston, Texas, in 2008. The Houston Chronicle wrote of him: a "song-and-dance man in the classic tradition, Denman is a natural scene-stealer."
In 2010 he choreographed and played the role of Artie in the Off Broadway premiere of Yank!: a World War II Love Story by Joseph and David Zellnik and was nominated for a 2010 Drama Desk Award for Best Featured Actor in a musical as well as a 2010 Lucille Lortel Award for Best Choreography.
He appeared as Lee Tannen in the World premiere production of I Loved Lucy, a play based on the best selling memoir by Lee Tannen, produced by the Laguna Playhouse in October 2010.
He played the role of Michael in John Kander & Greg Pierce's musical, Kid Victory in both the Signature Theatre world premiere as well as the subsequent Vineyard Theatre production. He received a Helen Hayes Award nomination, an Outer Critics Circle nomination and his second Drama Desk Award nomination for his performance.
In 2016 he founded Denman Theatre & Dance Co.
He is the author of A Year With The Producers:One Actor's Exhausting (But Worth It) Journey from Cats to Mel Brooks' Mega-Hit (Routledge, 2002).
Denman and Erin Crouch were married in August 2008. Divorced 2014
Kid Victory (musical) (Off Broadway Cast Recording)
Passion (musical) (CSC Off Broadway recording)
Face the Music (Encores! Cast Recording)
Irving Berlin's White Christmas (Studio Cast Recording)
Stage Door Canteen: Broadway Responds to World War II (92nd Street Y Concert Cast Recording)
The Producers (Original Broadway Cast)
How to Succeed in Business Without Really Trying (1995 Revival Cast Recording)