When the nation's first black president steps onto the Edmund Pettus Bridge to honor the marchers beaten there 50 years ago, he'll be standing on a structure that's at once synonymous with the civil rights struggle and a tribute to a reputed Ku Klux Klan leader.

The latter fact had all but faded from local memory until recently, when a Selma student group launched an online petition to rename the landmark bridge.

During his 50th anniversary address Saturday, President Barack Obama will be flanked on one side by a new historic marker commemorating "Bloody Sunday," when white police beat demonstrators marching for black voting rights on March 7, 1965. The sign, erected earlier this year by the state tourism department, notes Obama's 2007 appearance there just before his election and the accolades for "Selma," the recent film about the march.