The Politico headline says it all: McCain weighs a Lieberman surprise.

John McCain is seriously considering choosing a pro-abortion-rights running mate despite vocal resistance from conservatives, with former Democratic vice presidential nominee Joseph I. Lieberman (I-Conn.) very much in the mix, close McCain advisers say.

Under strong consideration: former Pennsylvania Republican Gov. Tom Ridge, and Lieberman, who was Al Gore’s running mate in 2000.

Multiple GOP sources say that party officials in Washington and in the states have been contacted by the McCain campaign in the past two weeks and asked about the fallout from such a choice. One person familiar with the calls said the party was being instructed to prepare for different candidate prototypes — including one in the mold of Lieberman, who is an independent but still caucuses with the Democrats.