The “Occupy Wall Street” protests, still a small group of several hundred people even in their third week, could be poised to grow a lot bigger. Several major unions have pledged their support and plan to join in coming days. On Tuesday, more than 700 uniformed pilots joined in the demonstration, demanding better pay. And on Wednesday night, the executive board of the New York Transit Workers Union voted unanimously to support the protest. The union then took to Twitter to urge its 38,000 active members to march on Wednesday, Oct. 5, in a demonstration sponsored by another eight labor and community outreach organizations. “They’re voicing our message, why not join them?” the TWU Local 100 spokesman told The Village Voice.