One of the ideas that permeates the abortion debate in so many ways is that supporting abortion rights is a minority position.
You see this partly in the idea that the law is cucrently 'outdated' (which is common even among those trying to change the law) as if it reflected it's time. Chris Trotter also strongly implied it - with the idea that hundreds of thousands of decent well-meaning people were behind the law as it stands now.
This is untrue - the current abortion law was wildly unpopular when it passed. 318,820 voting aged people signed the REPEAL petition (much like it sounded a petition to repeal the restrictive abortion laws) in 13 weeks. When you think about how many CIR have struggled to get that number of signatures - let alone that percentage of the population, you will understand it was a staggeringly unpopular law.
In this thread (warning the original post makes Chris Trotter look like a hardcore supporter of a woman's right to choose) the idea that abortion is a minority position bandied about by both supporters and opponents of law change.
Gaging public opinion on abortion is always difficult - the way the questions are worded makes a huge different to the way people answer them. But support for women having access to abortion is solid, and support for denying access to abortion is not.
More importantly in the 1970s public opinion on abortion swung very quickly. There are probably many reasons for this, but the most important is that women were speaking openly about their experiences of having an abortion and claimed abortion as a right - this position quickly resonated with people.
Those who support a woman's right to choose are not a minority, and the best way to build our movement is to make sure we don't act like one.