Yes, certainly. Most Catholics already support it. Just give it time for today's young people to enter the priesthood and work their way up through the ranks.
This is just anecdotal, but I get the impression the younger priests are more conservative than the boomers. I think it's more likely that people will stop identifying as Catholic than become priests. Being against church teaching usually isn't a positive indicator of one's desire for the priesthood.
The Church still teaches that contraceptives are sinful. I'm having trouble understanding why y'all think Catholic gay marriages are somehow inevitable.