"Oh yes, we are well aware of Senator Obama’s morally unacceptable position on abortion. No Catholic can or will endorse the taking of innocent life. Indeed, conscience could not just dissuade, but directly preclude, casting a vote in his column. However, Catholic moral teaching enjoins us to work to transform the culture in every vineyard, not just those that are friendly. And Senator Obama has courageously and intriguingly opened a window of opportunity for important conversation across faith traditions, by reminding us that "we should not use faith as a wedge to divide, but instead use faith to resolve cultural tensions and mediate conflicts rather than engage in a politics that exploits them and drives us further from a solution ...
To date, Senator Obama has kept the essence of his campaign at the level of the statesmen, which is why many Catholics, including myself, find this to be a favorable comparison to the memory of Ronald Wilson Reagan," - Douglas Kmiec, responding to Ramesh Ponnuru, in NRO.
His orthodox Catholic defense of Obama over McCain can be read here. I don't agree with all of Kmiec's views, but I do believe that Obama's sensibility and public conduct are appealing to most of the Catholics I know.