The answer is in the details.
As a senator from Tennessee from 1994 to 2002, Thompson's voting record indeed shows he compiled a perfect record on voting against abortion rights, cloning and certain research that many antiabortion advocates find objectionable.
He voted against a resolution supporting Roe v. Wade, the landmark 1973 Supreme Court case that requires all states to permit abortion. Several times, he voted for a ban on late-term abortion, called partial-birth abortion, except when the life of the woman -- not her health - is at stake. He supported a ban on abortions in U.S. military hospitals and clinics, voted to block federal funding for assisted suicide, and voted to make it a federal crime to transport a minor across state lines for an abortion.
So what's with the middling marks from the National Right to Life Committee's grade, then? The Washington-based group, which boasts 3,000 chapters in all 50 states, ranks members of Congress each year on their votes.
But Thompson was docked not for his votes on so-called "life issues;" instead, he lost points for supporting a series of campaign finance reform bills that sought to limit the contributions or advertising of outside interest groups. Many advocacy organizations opposed these reforms because they feared they'd lose influence in Congress.
In 1995, he also supported a welfare reform bill the group opposed, said David O'Steen, executive director of National Right to Life.
But on matters dearest to their members' hearts, Thompson is right on, O'Steen said. He also voted with the group against cloning and fetal tissue research, and for limits on how federal funding could be used for family planning activities abroad, his voting record shows.
In fact, the National Right to Life Committee has endorsed him for president.
"It's very fair for him to say that on every bill that came forward, he cast a pro-life vote," O'Steen said. "I think he's fairly characterizing this. He's got a very pro-life record, and that was a big part of our endorsement –- it's not just talking the talk, but walking the walk. He was there, and he wasn't one of the members that vacillated and you wondered where he was going to be. He was solid."
The ad, which aired first in Iowa, then nationally on Fox News, is designed to help Thompson set himself apart from his chief Republican rivals, former Massachusetts Gov. Mitt Romney and former New York City Mayor Rudy Giuliani, in the race for the GOP nomination. Romney says he now opposes abortion; when he ran for governor, he said he was in favor of abortion rights. Giuliani publicly supports abortion rights.
By contrast, Thompson's commitment in public life to the policies espoused by antiabortion groups has never wavered. We find his claim True.