Democratic presidential candidate Barack Obama is harshly accusing a pro-life group of "lying" about his record on abortion as a Illinois state senator, despite compelling evidence on the pro-lifers' side.

Obama made the aggressive attack when Christian Broadcasting Network Senior National Correspondent David Brody asked Obama about documentation the National Right to Life Committee recently obtained of a 2003 committee vote on “born alive” legislation that would have required medical officials to give life-saving care to babies who survived abortion.

Obama has said again and again he voted against versions of that bill as an Illinois state senator because it did not include language to protect Roe v. Wade, as the federal version did which sailed through the U.S. Senate 98-0. The committee report, however, shows a 10-0 vote in favor of an amendment to add the same language to protect abortion rights that was added to the federal bill. That same committee report subsequently shows Obama voting the kill the bill in a "final action" vote.

The committee report is also verified by an Associated Press story.

“There was some literature put out by the National Right to Life Committee,” Brody told Obama in an interview that took place Saturday night. “And they’re basically saying they felt like you misrepresented your position on that bill.”

Obama said the NRLC “have not been telling the truth” and launched into some of the most vicious language he’s ever used against his opponents. “And I hate to say that people are lying, but here's a situation where folks are lying,” he lectured.

“It defies common sense and it defies imagination and for people to keep on pushing this is offensive and it's an example of the kind of politics that we have to get beyond,” Obama said. “It's one thing for people to disagree with me about the issue of choice; it's another thing for people to out and out misrepresent my positions repeatedly, even after they know that they're wrong. And that's what's been happening.”

Brody published a video of the interview on CBN.

Douglas Johnson, NRLC’s legislative director wants Obama to apologize to his group or prove the documents they obtained are erroneous. Obama must “either declare the newly discovered documents to be forgeries and call for an investigation of the forgery, or admit that he had misrepresented his record on the live-born infants legislation (not just once, but for four years), and apologize to those he's called liars," Johnson told Townhall in an email.

“We don't have an apology yet,” Johnson said.

An Obama spokeswoman, Hari Sevugan, grudgingly admitted Obama had indeed voted against the bill in committee to the New York Sun Monday. She said Obama voted against it because he wasn't convinced the bill would not be used to undermine abortion rights in the state of Illinois.

Johnson said brushed off Sevugan's explanation. "The newest line is also not consistent with Obama's oft-stated excuse for opposing the state legislation, and fails to explain his four years of misrepresentation," he said. "Nor does the Sun story indicate that the Obama campaign has issued any apology to NRLC, Bill Bennett, or the others who Senator Obama and his campaign have been calling liars for saying what they now admit was the truth."

Like the NRLC, conservative radio host Bill Bennett was attacked by the Obama campaign earlier this year for discussing Obama's record on born alive legislation.

Pro-lifers believe Obama’s 2003 vote would surely hurt him among social conservatives and evangelicals who may consider supporting him in November. Family Research Council President Tony Perkins said “there's no doubt” Obama supported “infanticide” by voting this bill down in committee.

“This is a radical position,” he told a small group of reporters at FRC's Washington headquarters.

Perkins joined the NRLC in calling on Obama to apologize to voters for "his misleading statements on life," in a statement released Monday afternoon.