WEST DES MOINES, IOWA ? GOP presidential hopeful Sam Brownback is best known for his sharp anti-abortion stance, but he said Friday that candidates will be successful only if they offer voters a balanced emphasis of fiscally and socially conservative values.

“We win on both wings of the party,” Brownback said Friday. “You can’t win on just one.”

On this day, though, the Kansas senator emphasized his stand on abortion.

Speaking to about 75 people at the opening of his Iowa headquarters in a suburban Des Moines strip mall, Brownback touted his long-standing opposition to abortion. Brownback promised that if elected president, he would appoint a Supreme Court justice who could tip to balance in favor of overturning Roe v. Wade, the 1973 decision legalizing abortion nationally.

“I’m a principled conservative that can get this done,” Brownback told reporters after the event. “I’ve got a track record on it. I have a pro-life track record, and a whole-life track record. I think that’s something that’s very much going to be embraced.”

Overturning the landmark Supreme Court case has been a key issue in Brownback’s underdog run for the GOP nomination. Earlier this week, his campaign announced it had received the endorsement of “Roe” in that case – Norma McCorvey, who now opposes abortion.

Though Brownback’s views mesh well with many social conservatives in Iowa, he has lagged in the polls behind front-runners Mitt Romney, John McCain and Rudy Giuliani.

Brownback has said his opposition to abortion would not prevent him from supporting a Republican nominee who supports abortion rights. But he said Friday he had qualms about many of the other candidates.

“You look at their track records and some are not pro-life,” he said. “I do not believe the party will nominate a pro-choice candidate.”

Brownback’s stop in West Des Moines came during a packed three-day jaunt to Iowa. Brownback planned to attend events today in Winterset, where he will participate in events marking the centennial of actor John Wayne’s birth in the community.

Brownback told supporters he would collect the endorsement of one of Wayne’s daughters and one of the actor’s grandchildren as well as march in a parade at the event.