The two will be the Pennsylvania co-chairmen of “ONE Vote '08,” an effort that is part of a national campaign led by former Senate Majority Leaders Tom Daschle (D-S.D.) and Bill Frist (R-Tenn.).

“Sen. Santorum has been for some years working with Bono and the ONE campaign on these issues,” Wofford said in an interview. “They asked him to be the co-head of the Pennsylvania effort, and he suggested that I should be his co-chair.”

The Democrat said he first learned of the organization from Daschle and became interested in the campaign. Wofford added that he and Santorum will begin recruiting a wide range of bipartisan and independent leaders throughout Pennsylvania to work on the campaign.

The two faced off in the 1994 Senate election and Santorum defeated the freshman incumbent.

Wofford said the two maintain a good relationship, especially after working closely together on faith-based initiatives in the early 2000s. “I enjoy working with him,” he said. “I think we both think it’s a good sign to people that you don’t take hard-fought political races personally, and you get on with the process of self-government in good spirit.”

“We see eye to eye on about 10 percent of things in politics,” Santorum said, “but we work very well on that ten percent. And that’s a good model.”

Santorum said that his Roman Catholic faith is a big motivation for his involvement in the ONE Campaign. “It’s vital,” he said. “Just because these people are halfway across the globe doesn’t make them any less important than people in America.”

The ONE Campaign is a national, nonpartisan organization started in 2004 by a coalition of groups with a shared interest in international development and relief issues. Since then, it has attracted a star-studded roster of supporters, including former politicians, rock star-cum-humanitarian Bono, and the Bill and Melinda Gates Foundation. The organization claims 2.4 million members worldwide, 2 million of whom are Americans.