Nicholas P. Cafardi, a civil and canon lawyer, and a professor and former dean at Duquesne University School of Law in Pittsburgh, is a pro-life, pro-Obama Catholic. He joins Doug Kmiec as another high-profile conservative Catholic to endorse Obama–and put himself at odds with a number of bishops.
Cafardi makes his case in a column for Religion News Service; the piece is posted at NCR. In it, Cafardi notes that the bishops have said that there are a range of issues that Catholics must consider when calculating how to vote, and while abortion is paramount, many other factors figure into that decision. He finds McCain wanting in this calculus:

How, some may ask, can I compare these evils with abortion? The right to abortion is guaranteed by the federal judiciary’s interpretation of the Constitution. And while the president appoints federal judges, the connection between a president’s appointments and the decisions rendered by his appointees is tenuous at best. After all, in 1992, five Republican-appointed justices voted to uphold Roe v. Wade in Planned Parenthood v. Casey. Yet on other intrinsic evils — an unjust war, torture, ignoring the poor — I can address those evils directly by changing the president.
There’s another distinction that is often lost in the culture-war rhetoric on abortion: There is a difference between being pro-choice and being pro-abortion. Obama supports government action that would reduce the number of abortions, and has consistently said that “we should be doing everything we can to avoid unwanted pregnancies that might even lead somebody to consider having an abortion.” He favors a “comprehensive approach where … we are teaching the sacredness of sexuality to our children.” And he wants to ensure that adoption is an option for women who might otherwise choose abortion.

Obama worked all of that into his party’s platform this year. By contrast, Republicans actually removed abortion-reduction language from their platform.
What’s more, as recent data show, abortion rates drop when the social safety net is strengthened. If Obama’s economic program will do more to reduce poverty than McCain’s, then is it wrong to conclude that an Obama presidency will also reduce abortions? Not at all.
Every faithful Catholic agrees that abortion is an unspeakable evil that must be minimized, if not eliminated. I can help to achieve that without endorsing Republicans’ immoral baggage. Overturning Roe v. Wade is not the only way to end abortion, and a vote for Obama is not somehow un-Catholic.
The U.S. bishops have urged a “different kind of political engagement,” one that is “shaped by the moral convictions of well-formed consciences.”
I have informed my conscience. I have weighed the facts. I have used my prudential judgment. And I conclude that it is a proper moral choice for this Catholic to support Barack Obama’s candidacy.

Cafardi is also one of the original members of the National Review Board, the blue-ribbon panel of lay Catholics created in 2002 to keep an eye on the bishops’ compliance with sexual abuse safeguards. So he is no stranger to controversy. His most recent book, Before Dallas, examines the bishops’ failures in handling the clergy sex abuse crisis.