According to the Toronto Star:  "[Working Ontario Women is] Bankrolled by the powerful Service Employees International Union"

https://www.thestar.com/news/queenspark/2017/10/12/working-ontario-women-organization-plans-pre-election-ad-blitz.html

In Ontario the SEIU predominately represents healthcare workers, so public sector union using tax dollars to try to convince people how to vote.  Illegal in many jurisdictions, but not Ontario.