Campbell attended the Collace Primary School and Perth Academy. She then studied at Glasgow University political science, economics and social history and graduated as Master. Subsequently, she worked as an editor. Campbell lives with her husband and son in Biggar.
In the years 2005 and 2006 Campbell worked for the SNP MPs Nicola Sturgeon and Shona Robison. For the first time Campbell joined the 2007 parliamentary elections to elections at the national level. In her district of Clydesdale, she received the second highest share of votes behind Labour candidate Karen Gillon and thus missed the direct mandate of the constituency. Since Campbell was, however, also set to the Regional Evaluation of the SNP for the election Region South of Scotland, she received as a result of the election results is one of five list mandates of the SNP in this election region and moved into the Scottish Parliament. In the 2011 parliamentary elections they then won by a clear margin the direct mandate of the constituency of Clydesdale. In the newly formed Cabinet Campbell has held the position as Secretary of State for Children and Youth.