The D.C. Council Chairman won the backing of both the police and firefighters’ union Thursday in his bid to unseat Mayor Adrian Fenty. The support of the public safety unions might help Gray counteract Fenty’s sizable campaign war chest. The Fraternal Order of Police union took veiled shots at Fenty’s leadership in its statement endorsing Gray. “Vincent Gray understands that public safety cannot be compromised for political gain,” the FOP said.