Arthur Watson is 43 and operates a small business in Saint John.
The Nov. 17 byelection was called after Liberal Gary Keating quit politics just three weeks after the provincial election, saying the hours and travel that come with the job would have a negative impact on his health and family.
New Democrat Leader Dominic Cardy will run for his party.
The Greens have chosen Sharon Murphy, who was their party's candidate in the Sept. 22 election.
Saint John Deputy Mayor Shelley Rinehart is running for the Liberals while Glen Savoie, who lost the election in that riding by nine votes, will represent the Opposition Progressive Conservatives.