A gay couple married under state law cannot give a joint contribution to a federal candidate if they make it from an individual banking account, the Federal Election Commission voted unanimously Thursday. In a somewhat emotional session, FEC commissioners lamented the fact they had no choice but to deny gay couples the same rights as straight ones, given the Defense of Marriage Act‘s legal requirements. Dan Winslow, a Republican candidate in next week’s primary for the open Massachusetts Senate seat, had requested the advisory opinion. “Mr. Engle, sometimes the law’s an ass,” declared FEC chair Ellen L. Weintraub, referring to the line from Charles Dickens’ “Oliver Twist” in addressing Winslow’s attorney Craig Engle.