In 2008, Johnson won the general election with 4,372 votes (52.6%) against Republican nominee Martha Sturtevant.[3]
In 2010, Johnson won the Democratic primary with 791 votes (68.1%),[4] and went on to win the general election with 6,402 votes (63.2%) against Republican nominee Kathleen Rokosz.[5]
In 2012, Johnson won the general election with 6,937 votes (69.2%) against Republican nominee Matthew Brown.[6]
In 2014, Johnson won the general election with 3,562 votes (61.4%) against Republican nominee Matthew A. Brown.[7]
In 2016, Johnson was unopposed in the general election, winning 8,703 votes.[8]
In 2018, Johnson won the general election with 5,864 votes (62.9%) against Republican nominee Daniel Zitofsky and Libertarian nominee Cody G. McNutt.[9]