I found this column by Michael Gerson in the Washington Post, dated 2 April 2008, through Catholic World News.
One quote from the column:
But Obama's record on abortion is extreme. He opposed the ban on partial-birth abortion -- a practice a fellow Democrat, the late Daniel Patrick Moynihan, once called "too close to infanticide." Obama strongly criticized the Supreme Court decision upholding the partial-birth ban. In the Illinois state Senate, he opposed a bill similar to the Born-Alive Infants Protection Act, which prevents the killing of infants mistakenly left alive by abortion. And now Obama has oddly claimed that he would not want his daughters to be "punished with a baby" because of a crisis pregnancy -- hardly a welcoming attitude toward new life.