Arthur "A.B.'' Culvahouse, a prominent Washington attorney who served as White House counsel to President Ronald Reagan during the president's final two years and led Sen. John McCain's search for a running mate - a search that included a "long list'' of 26 candidates - told the tale today of picking Alaska Gov. Sarah Palin. After the vetting of all the candidates, and paring them to a short list, McCain asked Culvahouse for the "bottom line'' on Palin. ""I said, 'John, high risk, high reward,''' Culvahouse said today. "His response - 'You shouldn't have told me that. I've been a...