Changing attitudes about same sex marriage admittedly, to some degree, required changing attitudes among some self-described liberals. Whether due to concerns about the politics of it or actual personal opposition for whatever reason, there was a time when not all politically engaged liberals were on board with it.
I've always thought one success of the liberal blogosphere, especially back in the day, was to knit together a more coherent liberal coalition on a broad range of issues. Don't always love what unions do? Fine, but labor rights are still necessary. Your religion opposes gay marriage? Fine, but equality in the eyes of the state is important. That kind of thing.
It's clear in this glorious age of Obama that liberals don't exactly agree on everything, but I do think liberal blogs did, for awhile at least, help get people on board with a broader agenda of social and economic justice.
