GOP Rep. Todd Akin said Monday that he doesn't plan to drop out of the Missouri Senate race after his Sunday comments about "legitimate rape" prompted criticism from at least five Republican Senate candidates and presidential contender Mitt Romney.

"I've really made a couple of serious mistakes here that were just wrong, and I need to apologize for those," Akin said on Mike Huckabee's radio show Monday. "Rape is never legitimate; it's an evil act that's committed by violent predators."

In a local TV interview Sunday, the six-term congressman defended his stance that rape victims should not have access to legal abortions because women rarely get pregnant from rape. "If it's a legitimate rape, the female body has ways to try to shut that whole thing down," he said, prompting a firestorm of controversy.

Akin said Monday that by "legitimate rape," he meant "forcible rape." He said he understood that rape could result in pregnancy, and told Huckabee that he personally knew some victims of rape. "I know it's a terrible, terrible thing."

Akin added that he has no plans of dropping out, despite heavy criticism from Mitt Romney and other members of his party. Massachusetts Sen. Scott Brown has called on him to step aside. "I'm not a quitter," Akin said. "I don't know that I'm the only person in public office who suffered from foot in mouth disease here. ... I've not yet begun to fight."

Sen. John Cornyn, chair of the National Republican Senatorial Committee, said in a statement that Akin's comments are "indefensible." "I recognize that this is a difficult time for him, but over the next twenty-four hours, Congressman Akin should carefully consider what is best for him, his family, the Republican Party, and the values that he cares about and has fought for throughout his career in public service," he said. According to Politico, Akin is cutting an apology ad in an effort to save his campaign.

Akin added that no Republican has personally called him and asked to step aside. The congressman is beating Democratic incumbent Claire McCaskill in the polls by a few percentage points.