Kavanagh's first venture into electoral politics was a run for the New Democratic Party in the 1988 Canadian federal election in the riding of Ottawa West.
She finished third, behind Liberal Marlene Catterall and the incumbent, David Daubney of the Progressive Conservatives.
When Bay Ward incumbent councillor Mark Taylor retired in 2018, Kavanagh entered the race to replace him.
On election day, Kavanagh won 55% of the vote, easily beating Don Dransfield, the husband of the incumbent Liberal MP, Anita Vandenbeld.
[3] Kavanagh is married to Alex Cullen, who represented Bay Ward for many years on city and regional council and was also a Liberal-turned-NDP Member of Provincial Parliament from 1997 to 1999.