If you compare 8 years of PC rule - which resulted in a Sheppard line, and the 14 years of Liberal rule with a York Region Spadina extension and an Eglinton line - you have to give a strong advantage to the Liberals - by a factor of 2 or 3.
If you compare 10 years of Harper with then record amounts for transit to the 12 years of Chretien/Martin rule, you would give a very strong advantage to the Conservatives - maybe by a factor of 40 or more.
It's likely that in the mid 1990's to early 2000's, the price of oil was much lower (letting more people drive) and the 1990's recession caused transit ridership to drop and not recover even by the mid 2000's. There were concerns ridership would not recover.