Mauldin played with the Boston Junior Bruins of the Eastern Junior Hockey League in 1999 where he showed his talent and explosiveness on the ice while earning consecutive First All-Star Team selections and the Eastern Junior Hockey League MVP Award in 2000. In 2001, he moved on to UMass Amherst where he accumulated 94 points in 98 games and led the Minutemen to the 2003 Hockey East Championship game. After three successful seasons with UMass he joined the Columbus Blue Jackets who had selected him with the 199th overall pick in the 2002 NHL Entry Draft.
Mauldin made his NHL debut not long after the Ice Hockey East Championship and appeared in six games for the Blue Jackets. He played the 2004–05 season for the Syracuse Crunch, the Blue Jackets AHL affiliate, and finished 7th on the team in scoring with 27 points. During the 2005–06 season he was traded to the Minnesota Wild for defenceman Dustin Wood. He was then assigned to the Houston Aeros, the Wild's AHL affiliate.
In the 2006–07 season, Mauldin initially played with Bloomington Prairie Thunder of the UHL, before leaving to play in Sweden. Prior to the 2007–08 season, Mauldin attended the St. Louis Blues prospect development Camp. He was then signed to a free agent contract by the Binghamton Senators of the AHL. Mauldin was then signed by parent club, the Ottawa Senators to a one-year contract for the 2008–09 season but was reassigned to Binghamton for the year.
On July 3, 2009, Mauldin signed a one-year contract with the New York Islanders. In the 2009–10 season he led the Bridgeport Sound Tigers, AHL affiliate of the Islanders, in scoring with 54 points in 77 games. He made his brief Islanders debut in a 7-3 defeat to the Pittsburgh Penguins on April 8, 2010, before returning to the Sound Tigers for a quarterfinal appearance in the playoffs.
A free agent following the season, Mauldin signed a one-year contract with the Colorado Avalanche on July 2, 2010. After initially impressing at the Avalanche's training camp, Mauldin was reassigned to AHL affiliate, the Lake Erie Monsters, to start the 2010–11 season. He was later called up by the Avalanche, and in his first game on November 12, 2010, he scored his first NHL goal, which was short handed, in a 5-1 road win against Steve Mason of his former team the Columbus Blue Jackets. He was named the second star of the game. Mauldin continued to make an impact with the Avalanche from the fourth line, most notably scoring two goals and two assists in a 7-4 victory over the Minnesota Wild on November 28, 2010, to be named first star of the game. Mauldin remained with the Avalanche for a career-high 29 games and 10 points before he was later returned to help Lake Erie to their first post-season berth.
In the 2011–12 season, Mauldin failed to make the Avalanche out of training camp and was reassigned to Lake Erie. After a strong start with the Monsters, Mauldin was limited through injury before finishing with 59 games, to place third in Lake Erie scoring 34 points.
A free agent, Mauldin returned for a second stint in Europe signing a one-year contract with HC Fribourg-Gottéron of the Swiss NLA on July 23, 2012. At the beginning of the 2014 season Mauldin was named an assistant captain and on November 21, 2014 Mauldin signed a two-year extension with HC Fribourg-Gottéron.