I've always voted Democrat because of their greater commitment to science, education and the environment. But they really haven't seemed as strong on science and education lately.
Anyway, if the Party wants to further environmental causes, it really shouldn't try to do it via insane proposals. Which is why not a single Democratic senator voted for it when Cocaine Mitch said "Sure, let's give it a shot." It hurts the cause and nobody will take Democrats as seriously if/when a proper environmental protection bill or resolution does finally come around.