McCain Risks Alienating Conservative Base With VP Choice

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.

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As McCain contemplates his choices, he is deciding between the conventional conservatives like Pawlenty and Romney and the two pro-abortion rights picks, who could perhaps open the party to moderate voters who backed Hillary Clinton in the Democratic primaries.

Before the Democratic National Convention, polls showed that 30 percent of Clinton's 18 million votes were up for grabs -- they had not decided whether to shift their support to Obama. The McCain campaign has aggressively courted those voters with a series of television ads running this week to coincide with the Democratic convention.

Ridge and Lieberman, it's believed, could appeal to some of those voters. Ridge would help in Pennsylvania, a key swing state. And Lieberman would enforce McCain's reputation as a political maverick who has a history of building bipartisan coalitions.

Both men are close friends with McCain and have appeared frequently on the campaign trail with him, and both share his views on national security.

And both would trigger a brawl at the convention next week in St. Paul, Minn., the likes of which hasn't been seen at a Republican gathering since the 1964 nomination of Barry Goldwater, the last Arizona senator to be the party's standard-bearer.

"I see a fight at the convention over either," said Phyllis Schlafly, president of the Eagle Forum.

The choice of Lieberman would trigger an all-out war. Although he supports the war in Iraq and is therefore considered by some to be a "moderate," he has liberal views on social issues deeply important to the Republican base. He has taken positions at odds with the party on gun control, tax cuts, gay rights, abortion and the Supreme Court, including voting against conservative Justice Samuel Alito.