For months, KDAN, the lilliputian radio station on the eastern shore of Tomales Bay, appeared destined to vanish from the airwaves. Its owner, Jeff Cotton, a radio aficionado who has built small-town stations across the West, was scaling down his operation. He had spent nearly a year trying to offload it to the right buyer—someone who would preserve its eccentric spirit at a time when stations like his were routinely gobbled up by goliath religious…