In a more serious note, his statement is almost universally panned as just fucking stupid. I get what he's trying to say about there being different levels of rape (with the obvious other type being statutory rape between kids who are only a year or two apart and it's consensual), but (a) his knowledge of rape/pregnancy is very 18th century and has been disproven by that weird science thing and (b) we can't start parsing something like rape or it leads us into dangerous territory such as "she was raped but it wasn't a violent rape, so she should be okay" kind of thinking.
Interestingly, I feel the same way about "hate crimes". While I understand them from a legal standpoint, I think that a white guy being murdered for his wallet during a robbery is just as valid as a black man who is murdered because someone doesn't like the color of his skin. The penalties should be the same, regardless of intent as long as the severity (ie, first degree, second degree) remains the same.
I think we haven't really talked about this because I can't see anyone sticking up for him.