There's a story developing in the Colorado Senate race that could help explain this, coming from Ken Buck:

I am pro-life, and I’ll answer the next question. I don’t believe in the exceptions of rape or incest. I believe that the only exception, I guess, is life of the mother. And that is only if it’s truly life of the mother.

A 2005 rape case that Ken Buck refused to prosecute indicates that maybe his threshold for what is really rape makes him less pro-life than anti-woman.

When Weld County District Attorney Ken Buck refused to prosecute a rape case five years ago, he probably had no idea that anyone beyond a small circle of people would care. He learned otherwise quickly enough as the victim demanded a meeting with him (which she secretly - but legally - taped), organized a protest and made sure the media knew all about her plight.... The alleged rape victim is back and determined to be heard. She told her story to the Colorado Independent and provided the tape of their meeting, in which Buck appears to all but blame her for the rape and tells her that her case would never fly with a Weld County jury.... He said the facts in the case didn’t warrant prosecution. “A jury could very well conclude that this is a case of buyer’s remorse,” he told the Greeley Tribune in March 2006. He went on to publicly call the facts in the case “pitiful.” If he had handled it with a little more sensitivity, the victim, who does not want her name used, says it is possible she may have accepted the decision and moved on. But Buck’s words — as much as his refusal to prosecute — still burn in her ears. “That comment made me feel horrible,” she told the Colorado Independent last week. “The offender admitted he did it, but Ken Buck said I was to blame. Had he (Buck) not attacked me, I might have let it go. But he put the blame on me, and I was furious. I still am furious,” she said. It wasn’t just his public remarks that infuriated the woman. In the private meeting, which she recorded, he told her, “It appears to me ... that you invited him over to have sex with him.” He also said he thought she might have a motive to file rape charges as a way of retaliating against the man for some ill will left over from when they had been lovers more than a year earlier. Buck also comes off on this tape as being at least as concerned with the woman’s sexual history and alcohol consumption as he is with other facts of the case.

You can read the transcript [pdf] of the meeting at that link. This part particularly stands out to me:

Victim: His statement says, “When he finished, ... (reading police report)... tried to get the victim to wake the victim up so he could apologize.” How is that not “physically helpless, meaning unconscious, asleep, or unable to act” (legal

code) KB: Because when you look at what happened earlier in the night, all the circumstances, based on his statements and some of your statements, indicate that you invited him to come to your apartment... that you told him how to get in .... It would appear to me and it appears to others that you invited him over to have sex with him. Whether that you, at that time, were conscious enough to say yes or no... ?

She was incapacitated, her alleged rapist told the police she was incapacitated. And Buck tells her it was her fault because she had a prior relationship with the man and invited him to her apartment. And if she was inviting him to her apartment it was to have sex with him. She asked for it, in other words.

Here's a question for Buck, who doesn't believe in abortions for rape or incest victims. Does Buck believe in acquaintance rape? Or is the woman always asking for it?