I'm not defending his position at all, but rather criticizing the logic employed by the blogger, implying that if Santorum is pro-choice in any circumstance, he should be pro-choice in all circumstances. Not trying to cover morals, just the logic employed by the blogger.

EDIT: I typed the last bit in a hurry, so allow me to clarify. If the blogger's message had been, "Ric Santorum is a hypocrite for stating he opposes abortion in all cases but making an exception for his wife whose health was in jeopardy," it would have been a valid argument. It would neither have proved or disproved the morality of abortions in any circumstance, but would have identified him as a hypocrite. However, that's not what the message of the blog was. Instead, its message was, "Ric Santorum opposes abortion in all cases except when health is at risk, as evidenced by his wife's abortion when her health was in jeopardy; Ric Santorum thereby shows the need for choice, thereby supporting pro-choice." This is an either-or argument: either you are completely against abortion or you are in favor of choice, and if in favor of any choice, you should be in favor of all choices.