Listen, while this statement is one of vile ignorance, there is something that everyone is missing.
While it's politically correct to lump all rape into the same act, unfortunately, in reality we know there are differences between a college girl that gets drunk and flirts heavily with a jock fratboy that ultimately ends up raping her, and a woman walking down the street, kidnapped at gunpoint, taken to a remote building, raped, and then thrown back on the street.
The analogy is this. Lets say, I have a million dollars, and I'm walking down the street, someone comes up to me, points a gun at me, and says, lets go to your bank and you will withdraw your million and give it to me. That is one kind of robbery.
Now lets say, I paste the money all over me, walk down the street and boast how rich I am, and flaunt it, of course I HAVE THE RIGHT to do it, and it doesn't JUSTIFY being robbed... but if I was robbed, whats the first thing that ANYONE in their logical mind would ask me: "Uhh why did you paste it on your body and walk around boasting it?"
Rape, Robbery, Assault, Murder, Arson, are all CRIMES. And no one is ever justified in doing them, thats why our legal system labels them as CRIMES. in all cases though, there are certain steps one can take to mitigate those from happening. Akin was likely alluding to those cases in which all mitigating steps were taken, and there is no way of interpreting any kind of invitation (not to get raped of course, but of any kind of sexual interest at all).
Now before the people clamor "how dare you? boo! blame the victim" just check out one of the geniuses of our time:
Louis CK is a special person, however, I don't think he just happened to run into the ONLY woman in the entire world who thinks this way.
So, while it's PC to look at this in a clear black and white lens, lets try and expand our thinking, even if the person who's causing us to do so is a complete fool that doesn't know how to pick the right words when he speaks.