Doug Wright’s “I Am My Own Wife” won the Pulitzer for drama last week, and the question is how much the award will have an impact on its commercial prospects. “In the last decade only two plays have won the Pulitzer while running on Broadway, and both eventually made back their investments. But this evidence is by no means conclusive. The 2002 winner, “Topdog/Underdog,” opened the same week it won the award, so it is difficult to discern the effect the prize had on sales. And in 2001 “Proof” received only a slight bump.”