firehouse primary
n.— «In most caucuses, voters debate party platform resolutions, elect local party committee members and then divide into groups according to their Presidential preference. The only item on the Michigan caucus agenda, however, is the Presidential voting, and in that sense, it more resembles a primary than a caucus. “It’s a firehouse primary disguised as a caucus,” Mr. Blumenthal said. “It’s legal even though it’s unfair.”» —“Mondale Is Victor In Michigan Vote; Also In Arkansas” by Phil Gailey New York Times Mar. 18, 1984. (source: Double-Tongued Dictionary)