Campbell is the current Chairman of the Ulster Unionist Party, having served as Vice Chairman in 2005. He was elected to Lisburn Borough Council in 1989 and served until 1993. Campbell also contested the selection meeting in South Antrim following the death of Clifford Forsythe.
The selection was marred by internal division, with South Antrim Modern Language Association Duncan Shipley-Dalton claiming that UUP Headquarters were trying to foist Campbell on the constituency.
Shipley-Dalton pulled out and Campbell lost out to anti-agreement candidate David Burnside. Between 2005 and 2012 he was Chairman of the Ulster Unionist Party.
In the run up to the Ulster Unionist Party leadership election, 2012 both candidates made clear that he would be replaced. lieutenant was announced in April 2012 that Lord Empey would become Chairman.
Elected Member of Northern Ireland Forum in 1996, where he was Chairman of the Agriculture and Fisheries Committee. Was a member of Ulster Unionist Party Talks team in the All-Party negotiations that led to the Belfast Agreement.