In a statement and a Tweet, conservative congressman Todd Akin says he "misspoke" during a local TV interview in which he made comments about "legitimate rape" and abortion. NBC's Kelly O'Donnell reports.

Updated 8:55 p.m. — A Republican Senate nominee found himself in hot water on Sunday for suggesting that instances of "legitimate rape" rarely results in pregnancy.

Rep. Todd Akin, a Republican who's locked in a hard-fought campaign in Missouri to unseat Democratic Sen. Claire McCaskill, was answering a question regarding his position on abortion rights in instances when a woman is a victim of rape.

"People always want to make it into one of those things — well, how do you slice this particularly tough ethical question," Akin said in an interview on KTVI-TV, video of which was circulated by the Democratic super PAC American Bridge.

Todd Akin on the The Jaco Report August 19, 2012 Watch on YouTube

“First of all, from what I understand from doctors, [pregnancy from rape] is really rare. If it’s a legitimate rape, the female body has ways to try to shut that whole thing down," Akin said.

Regarding his opinion on whether to allow for an abortion in such instances, Akin added: “But let’s assume that maybe that didn’t work or something. I think there should be some punishment, but the punishment ought to be on the rapist and not attacking the child.”

Akin's comments had an almost immediate impact on Missouri's Senate race. McCaskill wrote on Twitter:

As a woman & former prosecutor who handled 100s of rape cases,I'm stunned by Rep Akin's comments about victims this AM bit.ly/NahiHz — Claire McCaskill (@clairecmc) August 19, 2012

In a statement, Akin said that he had misspoken.

"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," he said.

Akin emerged earlier this month from a tough three-way primary in Missouri, where he rallied social conservatives behind his candidacy. Democrats actually spent during that primary to help Akin win, viewing the six-term congressman as a less formidable challenger in the general election.

McCaskill, who was first elected in 2006, has become a top target for Republicans this fall, given President Barack Obama's unpopularity in the state and successive statewide victories for the GOP.

Presumptive Republican presidential nominee Mitt Romney's campaign issued a statement disagreeing with Akin.

"Governor Romney and Congressman Ryan disagree with Mr. Akin’s statement, and a Romney-Ryan administration would not oppose abortion in instances of rape," said Romney spokeswoman Andrea Saul.

Republicans need a net gain of four seats this fall in order to take over the Senate in the next Congress, and Democrats must defend 23 seats this fall. But unexpected Republican retirements and races that have become more competitive than expected have boosted Democratic hopes of maintaining their majority.