Hopefully we'll follow suit next year
I doubt it. Argentina has an influential Church. Uruguay is 75% atheist and even the conservatives support the law according to polls.
They aren't really that influential anymore, despite their staunch opposition Gay marriage was passed relatively easy and with a great majority of the population supporting it. Of course it won't be easy since abortion is a much more controversial topic than gay marriage but again, it's a slow improvement. Also there's the fact that the government apparently supports an abortion law and since they are growing used to passing whatever the hell they want it's not a long shot it will be legalized in the near future.
Didn't the law pass 50-49 in the lower house over there? at least that's what I read somewhere. So the support in the polls don't seem to have much influence in how the politicians vote. So, it's not like we'll have to wait for 80% of the people to support abortion to pass such a thing, and as far as I know support is growing as the years go by.
Oh, by the way, where did you get the figures for 75% atheism? All I could find was Wikipedia and that says that it's officially 17%.
However, I think the trend is pretty clear. At least this is being discussed now even in political debates, something that was mostly unheard of not even 10 years ago.