Norm Sterling's 34-year term representing Carleton-Mississippi Mills could come to an end Thursday night.
The Progressive Conservative nomination meeting puts Sterling against Jack MacLaren, former president of the Ontario Landowners Association.
"I think it's hard to stay fresh at any job for 34 years, especially politics," said MacLaren. "I'm sure Mr. Sterling did a great job in his early years, but in the last couple of years he's gotten somewhat complacent."
Sterling was unavailable for comment.
This provincial nomination fight has been fierce, at times creating a rift in the Conservative caucus.
Fellow PC MPP Randy Hillier has been accused of using his website and legislative resources to try to help MacLaren.
It even drew a complaint from a Liberal MPP to the province's Integrity Commissioner. Hillier has denied he did anything wrong.
Sterling was first elected in June 1977 and served in various top positions in government including Attorney General, Minister of Justice and Government House Leader.
With a report from CTV Ottawa's John Hua
