In the wake of comments by CNN's Candy Crowley, who will be moderating tomorrow's presidential debate, that she was planning to ask her own follow-up questions to the ones posed by citizens that she calls on during the townhall-style event, Mark Halperin reported last night that both campaigns were expressing concerns to the Commission on Presidential Debates. Halperin says he was leaked a copy of the memorandum of understanding between the Obama and Romney campaigns, and that it explicitly limits Crowley's role in the following way. After each audience member question and two-minute response from each candidate: “In managing the two-minute comment periods, the moderator will not rephrase the question or open a new topic … The moderator will not ask...