Here is a comparison of what the leading candidates say about abortion on their "issues" pages of their campaign web sites. These are just excerpts but I have provided the links if you want to read all of what they say. [side note: I find in interesting that Hillary, Barack, and John all speak of their issues in the third person. Only Mike Huckabee uses first person.]
Clinton: Hillary has stood firm as an advocate for a woman's right to choose. … She spoke out forcefully against the Supreme Court's April 2007 decision that -- for the first time in decades -- failed to recognize the importance of women's health. [side note: is she afraid to say "Partial Birth Abortion Ban Act" for the way in which that describes the nature of this type of abortion?]... Hillary has fought the relentless and insidious efforts by far-right Republicans to limit the protections of Roe v Wade, while also working hard to expand access to family planning services. …
Obama: I can find nothing in the "issues" section of his web site regarding the issue.
McCain: John McCain believes Roe v. Wade is a flawed decision that must be overturned, and as president he will nominate judges who understand that courts should not be in the business of legislating from the bench. Constitutional balance would be restored by the reversal of Roe v. Wade, returning the abortion question to the individual states. The difficult issue of abortion should not be decided by judicial fiat. … Once the question is returned to the states, the fight for life will be one of courage and compassion - the courage of a pregnant mother to bring her child into the world and the compassion of civil society to meet her needs and those of her newborn baby.
Huckabee: I support and have always supported passage of a constitutional amendment to protect the right to life. My convictions regarding the sanctity of life have always been clear and consistent, without equivocation or wavering. I believe that Roe v. Wade should be over-turned. … I applaud the Supreme Court's recent decision in Gonzales v. Carhart forbidding the gruesome practice of partial birth abortion.[note the opposite sentiment expressed by Hillary]
Other recent comparison posts of mine: stem cell research, immigration, marriage, energy/environment, federal spending