Internet-based "online robots" now provide public access to remote locations such as museums and laboratories. The Tele-Actor is a collaborative online teleoperation system for distance learning that allows many students to simultaneously share control of a single mobile resource. Our goal is to preserve the educational advantages of field trips without the drawbacks of group travel. We propose the "spatial dynamic voting" (SDV) interface for multiple operator single robot (MOSR) teleoperation. The SDV collects, displays, and analyzes a sequence of spatial votes from multiple online operators at their Internet browsers. The votes drive the motion of a single mobile robot or human "Tele-Actor". The paper describes Version 3.0 of the system architecture, SDV interface, algorithms for automated goal selection, and metrics for collaboration and leadership. We report results from a July 2001 field test with 56 remote users.