Dark Horse by Frances Lucas

Fed up with the corruption in local politics, lesbian Sidney Garrett makes a long shot bid for mayor. Enter conservative and naïve 'society girl', Joan Stanford who volunteers for Sidney's campaign on the whim. She soon finds herself wanting more involvement-with the campaign and its issues and, strangely, with Sidney. Attracted to Joan as well, Sidney maintains her distance until election day draws near and events take surprising and unsettling turns as Joan and Sidney must make some unexpected choices.