Zack Exley, one of the smartest progressive online activists I know, has been maintaining a blog called "Revolution in Jesusland," about the evangelical resurgence, with an emphasis on bridging the gap between progressive activists and evangelicals. This is a laudable effort, and Zack's tackling it with wit, humility and a great deal of intelligence.
First, progressives will never achieve their goals as long as they are hostile toward and ignorant about the faith of 100 million of their own people who are born again Christians.
Second (and we know how difficult this is to believe) there is an incredibly large and beautiful social movement exploding among evangelicals right now that stands for nearly all of the same causes and goals that secular progressives do. Those goals include: eliminating poverty, saving the environment, promoting justice and equality along racial, gender and class lines and for immigrants–and even separation of church and state.
By learning to work together with "progressive" evangelicals, secular progressives will stand a better chance of achieving their goals and also learn an enormous amount from these remarkable people and their organizations that will help secular progressives strengthen their own movement.