Campbell was born in Corby, Northamptonshire. As a youth he played for hometown club Corby Town, before joining Leicester City, for whom he made his first-team debut in 1996 aged 18. Though manager Martin O'Neill rated him as an outstanding prospect, he averaged fewer than ten Premier League appearances a season for Leicester, mostly as a substitute. In 2000, he was loaned to First Division club Birmingham City, where he played two games before returning to Leicester. Leicester won the League Cup twice while Campbell was at the club. First in 1996-97 and again in 1999-2000. Both times he contributed two substitute appearances during the cup runs, and in the latter victory both of these came over both legs in the semi final against Aston Villa.
Grimsby Town
New Grimsby Town manager Lennie Lawrence made Campbell his first signing in September 2000, landing the winger on a three-month loan deal which was later extended to a season loan. After impressing while on loan at Blundell Park, Campbell was allowed to join Grimsby permanently for a fee of £200,000, where he signed a three-year contract. Campbell played under three different managers at Grimsby, Lennie Lawrence, Paul Groves and Nicky Law. His six goals in the 2002–03 season was enough to make him the club's joint top scorer; they were relegated from the First Division after a five-year stay in the second tier of English football. Campbell's contract expired at the end of the next season, and with the club again relegated, he decided against an offer to stay with Grimsby.
Bristol Rovers
Campbell signed for Bristol Rovers of Football League Two. Appointed captain in November 2006, Campbell led Bristol Rovers to the final of the Football League Trophy and promotion to League One in the 2006–07 season. One of his three goals for the club came in the play-off semi final against Lincoln City. He signed a two-year contract extension in May 2007. Campbell and team-mate Craig Hinton started studying for coaching qualifications in 2008. Campbell then led the team to the quarter finals of the FA Cup in the 2007–08 season and became one of the most popular skippers at the club. Following the dismissal of Dave Penney as manager, Campbell was appointed caretaker manager of Rovers until the end of the season, with 12 games remaining in which to avoid relegation from League One. He failed to save the club from the drop to League Two however, and when Paul Buckle was appointed as the club's new manager he made it clear that Campbell had no future as a player at the club. The two parties eventually agreed a deal to release Campbell from his contract on 20 December 2011.
Tampa Bay Rowdies
On 27 December 2011, the Tampa Bay Rowdies of the North American Soccer League announced that Campbell had signed with the club. He soon moved into the role of a player/coach under manager Ricky Hill, and when Campbell retired from the pitch in 2013, he became a full-time assistant coach. In August 2015, first-year Rowdies coach Thomas Rongen was fired after the club struggled to a 2–2–6 start to the NASL's fall season. Campbell was promoted to manager and led the team to a 3–4–4 record over their remaining games. He coached the Rowdies in 2016 and 2017, before he and the club mutually parted ways in May 2018.
