With Sen. John McCain poised to announce his vice presidential selection Friday at noon in Ohio, a revolt is brewing among anti-abortion activists in his conservative base that could include a walkout at the Republican National Convention next week and a huge battle on the floor -- especially if he selects former-Democrat-turned-Independent Joe Lieberman.
McCain campaign sources tell ABCNews that the presumptive Republican nominee will announce his pick for vice president at a scheduled event in Dayton, Ohio.
In addition to the possible brawl at the convention, major conservative donors who have planned to bankroll issue-oriented advertising and other grass-roots efforts directed at social conservatives are putting their work on hold and will withdraw financial support if McCain picks a running mate that is not strongly anti-abortion, sources told ABC News.
One conservative strategist characterized the prospect of an abortion rights pick as a "disaster" for the Republican Party -- and said selecting Lieberman would cost McCain the election. It would enrage conservatives and prompt some Republicans to shift support to libertarian candidate Bob Barr, the strategist said.
With the election so close, even a couple percentage points could make a difference.
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McCain told a Pittsburgh radio station this morning that he had not made a final decision, though sources within his campaign later reversed that claim.
This morning, sources told ABC News the timing of McCain's announcement had not been finalized -- and would not be settled until McCain made his choice. They said at the time that the pick could be revealed on Saturday or closer to the opening of the convention next week.
Two pro-abortion-rights contenders remain very much in the mix: Lieberman, who was Al Gore's Democratic running mate in 2000, and former Pennsylvania Gov. Tom Ridge. Either would mark the first time in modern history that an openly pro-abortion rights candidate for vice president was on the Republican ticket.
McCain also is considering Minnesota Gov. Tim Pawlenty, a popular two-term governor in a moderate state who would bring blue-collar roots and Ronald Reagan conservatism to the ticket.
The 47-year-old Pawlenty, who is an anti-abortion rights advocate, is in many ways the conservative version of Obama, but with executive experience: same age, similar backgrounds, same law school education and careers in public service. As governor, Pawlenty erased a deficit and balanced the budget while pushing through conservative programs.
McCain also is considering his former bitter rival Mitt Romney, a multimillionaire businessman who would bring economic experience but who was also harshly criticized by the Arizona senator and social conservatives during the primaries.
Romney, who is an anti-abortion rights advocate, was seen as flip-flopping on key social issues in a perceived effort to pander to the Republican base. Moreover, Democrats are already painting Romney, with his $30 million in residential real estate and offshore tax havens, as elitist and out of touch with everyday Americans.