Jan. 21, 2009
"Am I doing this again? ... My memory is not as good as Justice Roberts'."
Biden, alluding to Supreme Court Justice John Roberts, who flubbed a line during Barack Obama's presidential oath the previous day, before swearing in members of his senior staff. Obama, standing nearby, shook his head disapprovingly and gave Biden a stern poke.
The Screwups of Campaign '08: The Complete List.