Mike Smith, the mayor of Colchester County, is the first official candidate to lead Nova Scotia's third-party Liberals.
Smith, 41, launched his campaign Wednesday in Truro, saying he believes politics matters and he wants to send that message to Nova Scotians.
Michel Samson, MLA for Richmond, has been leading the party since June, when Francis MacKenzie resigned soon after the provincial election.
The Liberals failed to improve their standing in the legislature and rise above their third-party status. They hold nine of the 52 seats at Province House.
Other possible candidates for the Liberal leadership include Samson, Annapolis MLA Stephen McNeil and Halifax-Clayton Park MLA Diana Whalen.
Mike Savage, MP for Dartmouth, has said he won't run.
Liberal party members will pick a new leader in April in Dartmouth.