The 2013 news cycle came with nary a dull moment.
From the Boston marathon bombings, NSA leaks and same-sex marriage Supreme Court decisions, to the George Zimmerman verdict, government shutdown and health care exchange fiasco, there was an abundance of game-changing news this year in the United States, replete with a steady flow of provocative headlines. In this interactive timeline, Andrea Caumont and George Gao at Pew Research chart 20 of the biggest stories of the year, noting how the public reacted based on polls conducted in the aftermath of each event.