When the US Supreme Court legalised abortion on January 22, 1973, American politics entered a new phase.

Abortion became one of the most contentious issues, dominating many election campaigns.

Less than two years after the Roe vs Wade verdict, the Republican incumbent Senator Bob Dole attacked his Democratic opponent, a physician, for having performed an abortion.

This was the beginning of politicians using the abortion issue in their campaigns.

Republicans protect the unborn child

The Republican Party incorporated an anti-abortion stance in its platform, demanding that the rights of an unborn child should be protected in the Constitution.

Graphic posters drive home the pro-lifers's point

During the 1992 and 1996 presidential elections, the party hardened its anti-abortion line as it looked for support from the Christian Coalition.

Meanwhile, the Democratic Party has been broadly supportive of the pro-choice movement. President Clinton summed up his party's stance by saying abortions should be "safe, legal and rare."

However, Republicans are split over the issue. While the religious right-wing of the party still wants a complete ban on abortions, the moderates want to drop the anti-abortion stance from the party's platform. They believe that it is deterring female voters.

But Kate Michelman, president of the pro-choice lobbying group, National Abortion and Reproductive Rights Action League, says that since winning control of Congress in 1994, Republicans have voted 81 times to restrict abortion rights, winning all but 10 of those votes.

Republican rift

Pro-choice activists accuse the Republican Party of using its hold on Congress and many state legislatures to erode women's right to abortions. According to the National Abortion Reproductive Rights Action League, in 1997 alone 31 states adopted laws limiting abortion rights.

For the last year much of the debate has focused on a method of late-term abortion. Technically it is known as intact dilation and extraction. The pro-life lobby calls it partial birth abortion.

The method involves removing the living foetus from the womb before killing it. The pro-life lobby argues this amounts to infanticide.

Kate Michelman: the pro-choice campaign is suffering from apathy

Over the last year Congress has twice tried to introduce legislation to ban such late-term abortions, and twice President Clinton vetoed the bills on the grounds that they failed to make exceptions for cases where the mother's life was in danger.

The issue caused the rift in the Republican Party to surface again earlier this month, when pro-life party activists petitioned the Republican National Committee to deny party funds to any Republican politician supporting late-term abortions.

But although most Republican leaders want to outlaw the controversial late-term method of abortion, they still voted against the petition. They argued that withholding money from candidates not supporting the ban on late-term abortions could drive both centrist politicians and voters away from the party, threatening the party's majority in Congress.