There are valid reasons to re-examine the 1968 assassination of Robert F. Kennedy to determine if Sirhan Sirhan really acted alone, conspiracy proponents say. Paul Schrade, the labor adviser to Kennedy’s presidential campaign who also was wounded in the shooting that left Kennedy dead in Los Angeles 40 years ago, said today’s technology can help prove others were involved, the New York Daily News reported Monday. “I’m convinced we can make the case,” said Schrade, who is assembling a legal team to challenge the verdict that put Sirhan, now 64, behind bars. Shane O’Sullivan, author of “Who Killed Bobby?,” questions the verdict based on evidence he says shows multiple shots came from more than one direction. A security guard implicated by audio analysis of the shots has denied he shot Kennedy, the Daily News said. The Kennedy clan is reluctant to push to have the case reopened. Bobby Kennedy Jr. told the News that while he suspects the assassination of his uncle, President John F. Kennedy, may have been a conspiracy, he has “never seen particularly compelling evidence” that was the case in his father’s death. Sandi Gibbons, spokeswoman for Los Angeles District Attorney Steve Cooley, said while she didn’t know if prosecutors knew of the recent analyses, they “believe Sirhan’s conviction is valid and supported by the evidence presented to a jury at trial.”