"There would be a major revolt if it were Lieberman,"said Schlafly. "I just do not believe the Republican convention would nominate Lieberman. I just don't think they would accept it, no matter if McCain wanted it."
Ridge, too, would also trigger a fight because of his views on abortion rights, although he is more conservative on other issues important to the base.
Charmaine Yoest, president and CEO of Americans United for Life, said either pick would be deeply disappointing for the anti-abortion rights base and would bring disarray to the convention next week.
"There's been a lot of talk about what kind of response there would be. The worst thing that you can have at a convention that's supposed to be a party is to have people anxious to leave. You'd see people who weren't willing to wave signs. You'll see people sitting on their hands, looking at their watches and real, real disappointment.
Yoest said the anti-abortion movement was energized after McCain's "strong performance" talking with evangelical leader Rick Warren at his Saddleback Church and were pleased with the strong platform the delegates had just approved.
"There's an expectation of wanting to see the platform and the ticket match, and for there to be the same enthusiastic commitment to life," she said. "The mental image of placards being handed out at the convention for a candidate who stands for abortion -- instead of life -- just doesn't work."
No modern Republican presidential nominee has ever campaigned with an openly pro-abortion rights running mate. In 1980, Ronald Reagan tapped George H.W. Bush as VP, despite Bush's past opposition to a constitutional amendment to ban abortion -- but he didn't give him the spot until Bush agreed to fully embrace the anti-abortion rights agenda.
"It would be a terrible mistake. Every one of our nominees has been pro-life," Schlafly said. "It's sticking his finger in face of the pro-life constituency to pick someone who isn't pro-life."
Although Ridge has indicated in recent interviews that he would support McCain's policies, he has not said he would repudiate his pro-abortion-rights views. Lieberman not conceded that; he has been a strong advocate of abortion rights, repeatedly earning an 100 percent approval rating from abortion-rights groups.
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