It was a sweltering Sunday afternoon a few weeks ago at Camden Yards, over 100 degrees and counting. Both sweat and beer were flowing freely. The Orioles had just come from behind to beat the Yankees, their rivals for first place in the fiercely competitive American League East pennant race. Sandy Rosenberg, a veteran member of the Maryland House of Delegates and a lifelong Orioles fan, was walking in the parking lot alongside a man sporting a Yankee pinstripe uniform jersey.