In 2010, Heffernan won the three-way general election with 4,363 votes (51.9%) against incumbentRepublicanTom Kovach and Libertarian nominee Matthew Flebbe.[4] She was one of only ten candidates to defeat a sitting Republican in a state house race in 2010 according to Ballotpedia.[5]
In 2012, Heffernan won the general election with 7,502 votes (62.4%) against Republican nominee Eric Taylor.[6]
In 2014, Heffernan won the general election with 4,496 votes (63.4%) against Republican nominee Kyle Buzzard.[7]
In 2016, Heffernan was unopposed in the general election and won 9,545 votes.[8]
In 2018, Heffernan won the general election with 7,073 (65.3%) against Republican nominee Jeffrey Olmstead.[9]
In 2024, Heffernan won the general election with 8,766 (65.65%) against Republican nominee Michael Krawczuk.[10]