US Senate nominee Todd Akin says rape victims can "shut down" the pregnancy in 'legitimate' rapes

REPUBLICAN senatorial candidate Todd Akin has triggered a firestorm of criticism, including a rebuff from Mitt Romney's campaign, after he suggested that "legitimate rape" rarely causes pregnancy.

Romney, the Republican White House hopeful, and his running mate Paul Ryan have sought to distance themselves from Representative Todd Akin's comments on one of the most polarising issues in American politics.

"Governor Romney and Congressman Ryan disagree with Mr Akin's statement, and a Romney-Ryan administration would not oppose abortion in instances of rape," a campaign statement read.

Akin, a six-term congressman running against incumbent Democrat Senator Claire McCaskill, was asked in an interview that aired Sunday on St. Louis television station KTVI if there were any circumstances in which he would support a woman's decision to have an abortion.

Akin, who has said he's Missouri's most conservative congressman, indicated there may be an exception to his stance against abortion.

But, when asked if he supported abortions for women who have been raped, Akin said: "It seems to me first of all from what I understand from doctors that's really rare.''

"If it's a legitimate rape, the female body has ways to try to shut that whole thing down,'' Akin said of a rape victim's chances of becoming pregnant.

He also said he would prefer that punishment for rape be focused on the rapist and not "attacking the child.''

Akin spokesman Steve Taylor intially declined to comment Sunday, saying he had not yet seen the interview. The video has been posted on the station's website.

I misspoke in TV interview, says Akin

But within hours, Akin was forced to quickly back off from his comments, saying in an emailed statement to media that he "misspoke" during the interview, though the statement did not say specifically which points.

"In reviewing my off-the-cuff remarks, it's clear that I misspoke in this interview and it does not reflect the deep empathy I hold for the thousands of women who are raped and abused every year," Akin's statement said.

"Those who perpetrate these crimes are the lowest of the low in our society and their victims will have no stronger advocate in the Senate to help ensure they have the justice they deserve."

Akin also said in the statement he believes "deeply in the protection of all life and I do not believe that harming another innocent victim is the right course of action."

Earlier, McCaskill, who is seeking a second term, said in an emailed statement that she found the comments "offensive.''

"It is beyond comprehension that someone can be so ignorant about the emotional and physical trauma brought on by rape,'' McCaskill said.

"The ideas that Todd Akin has expressed about the serious crime of rape and the impact on its victims are offensive.''

McCaskill also quickly took to Twitter to decry Akin's comments, saying that "As a woman & former prosecutor who handled 100s of rape cases, I'm stunned by Rep Akin's comments about victims this AM.''

This month, Akin won the state's Republican U.S. Senate primary by a comfortable margin of victory.

During the primary, Akin enhanced his standing with TV ads in which former Arkansas governor and presidential candidate Mike Huckabee praised him as "a courageous conservative'' and "a Bible-based Christian'' who "supports traditional marriage'' and "defends the unborn.''

Akin, a former state lawmaker who first won election to the U.S. House in 2000, also has a long-established base among evangelical Christians, and was endorsed in the primary by more than 100 pastors.

-with AAP