Article Photos: AP Interactive: The 2012 Presidential Election 6/21

Mounted police stand guard near the Ritchie Center at the first 2012 Presidential Debate at the University of Denver, Wednesday, Oct. 3, 2012 in Denver. (AP Photo/The Denver Post, Helen H. Richardson) MAGS OUT; TV OUT; INTERNET OUT; NO SALES ORG XMIT: CODEN309