Since its beginning, West Hollywood has offered the country’s closest approximation of a gay city. It was founded by gay activists over 26 years ago, most of its City Council members are gay, and the community is famous for its concentration of gay residents and nightlife. But an uncommonly bitter election has exposed a growing divide over what West Hollywood should represent, with prosperity and urban development pitted against the city’s history as a countercultural haven. The six challengers in Tuesday’s City Council election — all of them gay men — are seeking to oust three incumbents by running on...