Senator Barack Obama delivered the 176th commencement speech May 25. Posted 06/03/08 When a pinch hitter comes into a game, it's usually a crucial moment — hope balanced against uncertainty. At Wesleyan's 176th Commencement May 25, the hope shone through, and by all accounts, the pinch hitter sent a grand slam far over the fences. "I have the distinct honor today of pinch-hitting for one of my personal heroes and a hero to this country, Senator Edward Kennedy," said U.S. Senator Barack Obama (D-Ill.). "He called me up a few days ago and I said that I’d be happy to…