Senator Jerry Hill urges the Santa Clara County Board of Supervisors to approve a clean Caltrain funding measure for the ballot, highlighting the urgent need for dedicated revenue to ensure the system's survival post-pandemic. He argues that attaching restrictions on the funds would undermine the intent of his legislation (SB 797) and could jeopardize the measure's viability and legality. Hill emphasizes that a clean measure has broad support and is crucial to prevent Caltrain's shutdown.