As head of the 800,000-member Los Angeles County Federation of Labor, Maria Elena Durazo is one of the nation’s most powerful union leaders, and a key player in the ongoing immigration reform negotiations. But before her current post, she led a hotel workers’ union. She said one of the hardest parts of the job was convincing workers who were in the country illegally to organize. They feared they could be easily fired, and she said that fear had rippling implications.