The album release of "At Folsom Prison" was prepared in four months. Despite the recent success of "Rosanna's Going Wild", a Cash single released just before the Folsom concerts that reached number two on the country charts, Columbia initially invested little in the album or its single "Folsom Prison Blues". This was due partially to Columbia's efforts to promote pop stars instead of country artists. Nevertheless, the single charted on the "Billboard" Hot 100 on May 25, 1968; it also hit the country charts a week later. The single suffered a setback when Sirhan Sirhan assassinated Senator Robert F. Kennedy on June 5, 1968. Radio stations ceased playing the single due to the macabre line: "I shot a man in Reno / Just to watch him die". Reeling in the success prior to the assassination, Columbia demanded Johnston remix the single with the line removed. Despite protests from Cash, the single was edited and re-released. The new version became a success, reaching number one on the country charts and the top forty on the national charts. The single prompted the album to climb the album charts, eventually reaching number one on the Top Country Albums chart and number thirteen on the Pop Albums chart—the forerunner to the "Billboard" 200. By August 1968, "Folsom" had shipped over 300,000 copies; two months later it was certified gold by the Recording Industry Association of America (RIAA) for shipping over 500,000.