Complex sentence: Deeply active in Liberal politics he was first elected to office in 1982 at age 19 when he won a seat on the board of the Carleton Separate School Board, at the time he was the youngest elected official in the province.
Split into simpler sentences: Deeply active in Liberal politics in his youth, he was first elected to office at age 19 when he won a seat on the Carleton Separate School Board in 1982. At the time, he was the youngest elected official in the province.