"When Republican John McCain announced charismatic first-term Alaska Gov. Sarah Palin as his running mate on Aug. 29, 2008, he re-energized his campaign. But it soon became clear that Team McCain had insufficiently vetted the ""hockey mom"" who was ill-prepared for the national stage and would arguably prove to be a liability — and a cautionary tale for future presidential candidates. History's 9 most surprising VP picks: A slideshow"