There is no rule with some exceptions. I would vote for any Democrat who voted against the War Against Terror. So if I were in Barbara Lee's district I would vote for her.
I would not vote for any Democrat merely on promises or on past performance in non-elected positions. She/he would first have to prove (by record) that his/her presence in a governmental position made an objective difference. Lee's solitary vote did make debate more possible on the issue. She made a difference. Subsequent votes against any Bush program have made no difference, material or symbolic.
There is no hope for progressive politics in the United States (including a better Supreme Court) until the DP loses its progressive voters.
Nathan is a real puzzle. He isn't stupid. He isn't a coward. He has very few reactionary positions (the only one I can remember is his offensive support of U.S. war crimes in Yugoslavia). He has an activist record to be proud of. So his absurd attachment to the DP is hard to explain or understand.
Carrol