Talk Left is spot on.
Sometimes it's important to stand on principle. The Senate failed to do this on the military commissions bill, and now, on the border fence bill. The Democrats got zilch in return. There was no advantage to their concession, except to appear to their constituents that they, too, are tough on crime and tough on immigration.
The left is simply not represented in Congress. We are still perceived as a liability. Centrism sucks. Values message or no values message, if being a Democrat means caving in on every issue that matters to me, from the death penalty to innocence issues to wiretapping to more mandatory minimum sentences to deporting those who have lived here for decades simply because they don't have proper papers, then what's the difference between the parties? Newsflash: There is none.
For years, I used to vote Democratic, but no more. The Greens in Vermont offer zilch. And the national Green Party has moved too much to the right for my taste (David Cobb Dems I call 'em). Not even local Democratic candidates deserve my vote. Even Bernie Sanders has been tainted by his linking to the Dems. I'm on the left for sure, though. In the upcoming election on November 7th, I'll probably vote for candidates in Vermont's Liberty Union Party.