Peggy Noonan caught it, as did, apparently everybody out in Denver:
"By the way, the best line of the convention so far? Ted Strickland of Ohio, when he echoed the 1988 Democratic convention joke about George H.W. Bush, that he was born on third and thought he hit a triple. Strickland said of George W. Bush that he was born on third and then stole second. It didn't get much attention in any of the commentary, but it's all people were talking about in the bars of Denver that night."