Sen. Timothy M. Kaine (D-Va.) listens as Democratic presidential candidate Hillary Clinton speaks during a campaign rally at Florida International University's Panther Arena in Miami on Saturday. (Mary Altaffer/Associated Press)

Eleven years ago, as he ran for governor of Virginia, Tim Kaine made clear his stance on abortion: “I have a faith-based opposition,” he wrote on his campaign’s website. “I will work in good faith to reduce abortions.”

Kaine went on to laud adoption as the best solution to an unwanted pregnancy. He promoted abstinence-only sex education (and later slashed funding to the program, citing research that found it wasn’t effective). He authorized the sale of “Choose Life” license plates to fund religious counseling clinics that discouraged abortion. He backed Virginia’s “informed consent” law, which requires women seeking the procedure to undergo medically unnecessary ultrasounds.

In short, he was conservative on reproductive issues, by his party's standards.

Kaine's past didn't stop Hillary Clinton — who wants to allow federal funding to cover low-income women’s abortion costs, among other progressive proposals — from naming Kaine her vice-presidential pick. He acknowledged one of their key differences in a Sunday email to supporters. “Hillary and I have different faiths,” he wrote, “but we share a common creed: Do all the good you can in all the ways you can.”

Kaine, who practices Catholicism, still personally opposes abortion. But news of Clinton’s freshly minted running mate didn’t outrage abortion rights groups. That's because Kaine has voted to defend access to the procedure since becoming a Virginia senator in 2012.

Ilyse Hogue, president of NARAL Pro-Choice America, noted his dramatic behavior shift. "While Senator Kaine has been open about his personal reservations about abortion, he’s maintained a 100% pro-choice voting record in the U.S. Senate,” she said in a statement. “He voted against dangerous abortion bans, he has fought against efforts to defund Planned Parenthood, and he voted to strengthen clinic security by establishing a federal fund for it.”

Planned Parenthood President Cecile Richards also praised Kaine on Friday during an MSNBC appearance, asserting, “He’s been not only a solid vote but really an ally."

Still, as Kaine’s profile rose this month, election followers expressed confusion: How can he disagree with abortion and fight to protect it?

Some Catholic leaders also have expressed disapproval, saying that a pro-choice stance is incompatible with the Catholic belief that life begins at conception.

"Senator Kaine has said, 'My faith is central to everything I do.' But apparently, and unfortunately, his faith isn’t central to his public, political life," wrote Bishop Thomas J. Tobin, of the Diocese of Providence, R.I., in a Facebook post on Saturday.

Kaine says he values individual liberty. He doesn't want to make personal decisions for half the nation's population. 

During his 2012 Senate race, he updated his website: "I strongly support the right of women to make their own health and reproductive decisions and, for that reason, will oppose efforts to weaken or subvert the basic holding of Roe v. Wade."

Still, he said he wants to reduce abortions. "The right way to do this," he wrote, "is through education and access to health care and contraception rather than criminalizing women's reproductive decisions."

In a debate that year, Kaine doubled down on this sentiment, asking his Republican opponent who wanted to outlaw abortion, “Why would you claim to be a small-government guy and propose such a dramatic reach into people’s lives and personal decisions?”

Opposing abortion while supporting a woman’s right to choose is not contradictory, said Katha Pollitt, author of “Pro: Reclaiming Abortion Rights."

“We all have beliefs that we wouldn't impose on others, because the social harm of enforcing such beliefs would be very great — illegal abortions, for example,” Pollitt said. “We believe other people also have a right of conscience. We don’t want government micromanaging people’s life. We believe in separation of church and state.”

She believes abortion advocates who hold a grudge against Kaine should drop it. “I think the pro-choice movement should welcome people who support abortion rights and access, even if they have personal reservations. There are plenty of Americans with that view.”

Roughly half of Americans say abortion is morally wrong, while 15 percent think it’s morally acceptable and 23 percent don’t consider it a moral issue, according to the Pew Research Center. Fifty-six percent, meanwhile, say it should be legal in most cases, compared with 41 percent who want it entirely banned.

The issue inspires intense feelings on both sides — and because the two major parties have assumed polar opposite stances, a national politician standing in the middle looks bizarre. Thomas White, an ethics professor at Loyola Marymount University, a Catholic school, said someone can be both a faithful Catholic and a public servant who is pro-choice.

"A Catholic public servant can readily have moral reservations about abortion yet still support laws that give women the freedom to choose," White wrote in an email. "In the United States, such principles as separation of church and state, freedom to worship (or not) as one chooses, and respect for the democratically enacted laws are sacred principles. In a diverse, democratic, secular society like America, politicians have a duty to respect these principles and to keep their religious convictions from interfering with their responsibilities as public servants."

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