Caccia's first wife, Mildred, was a candidate for the Ontario Liberal Party in a provincial election in the 1970s.
Caccia was one of only three cabinet members to endorse Jean Chrétien in the 1984 Liberal Party of Canada leadership election, along with David Collenette and Roméo LeBlanc.
Martin backed former Toronto city councillor Mario Silva for the Liberal Party nomination in Davenport.
Caccia pulled out of the race, and after some talk, chose to retire from politics rather than run as an independent or Green in the 2004 election.
In 1964, he was labelled as a communist by East York Mayor True Davidson for suggesting that Toronto city run day cares accept children from mothers in two parent working families.