admitted to The New York Times in 2001.

Brock went on to found the media watchdog group Media Matters for America.

Also appearing on NBC Sunday, former New Mexico Gov. Bill Richardson (D) called out Barbour's support for Mississippi's personhood amendment as an example of the way the Republican Party views women's rights.

"Sexual harassment is serious," Richardson declared. "We have to protect women in the workplace. I think Mr. Cain has to answer these questions. You know what is most disturbing is a Washington Post poll that I saw. Fifty-five percent of Republicans think this charge is not serious."

"I think it is important, also, that we look at how women are fairing in Republican primaries. Personhood amendments are sprouting out everywhere. The extreme right wing of the Republican Party has taken over to the point where we now have an amendment in several states that criminalize a woman's right not choose, that prevents in vitro fertilization, that prevents birth control, even in cases of rape and incest. I think what you are seeing is a huge assault on women's rights in the Republican Parties and an extreme right wing that has taken over."

Mississippi's Initiative 26 defines personhood as "every human being from the moment of fertilization, cloning or the functional equivalent thereof."

Recent polls suggest that the state constitutional amendment -- which critics say is a backdoor way to ban abortion -- will pass. Petitions have also been filed to put personhood amendments on the ballot in Ohio, California and Nevada.