Republican presidential candidate and U.S. Senator John McCain (R-AZ) greets people gathered at the former Lorraine Motel, now part of the National Civil Rights Museum, where Rev. Dr. Martin Luther King Jr. was assassinated in 1968 in Memphis, April 4, 2008. April 4 marks the 40th anniversary of the assassination of the civil rights leader shot as he stood on the balcony of the Lorraine Motel. REUTERS/Mike Segar (UNITED STATES)