ATLANTA (AP) — With less than half a day left to live, Troy Davis faced execution Wednesday despite a furious campaign in the U.S. and Europe to win clemency for the 1989 slaying of a Georgia policeman he claims he did not commit. Supporters planned vigils outside Georgia's death row prison in Jackson and protests at U.S. embassies in Europe. Davis' attorneys lost a bid to give him a polygraph test to prove his innocence but planned another late appeal, this one aimed at blocking the execution by convincing a judge that some of the original evidence was questionable.