Abstract: A compact, versatile voting machine is disclosed having adaptability for use with various vote registering devices such as tally counters and punch card apparatus. The voting machine includes a selector mechanism having a series of parallel columns housing voter operated key slides. A vertical interlock mechanism includes ball housing blocks which are alternately disposed between the key slides and house displaceable interlock balls in a tool line. The cam blocks are adjustable to limit the effective length of the tool line to establish groupings of candidates from which a single selection can be made. A magazine at the top of each column is adjustable to permit multiple selections from a grouping. Actuation of a key cams the interlock balls into the tool line, and when a predetermined number of voter selections have been made no additional keys can be actuated as they are blocked by the tool line.