In case this is news to anyone, political power is not a function of being able to convince others using reason to follow a particular path. Political power may flow from elections and democratic institutions but, as we are currently constituted in the United States, this is not the case. We have a President that can still do pretty much as he pleases whether he has an 80% or 20% approval ratings and whether or not his party has a majority in Congress. There are reasons for this that come down to this: as a practical matter if you can control what is "real", i.e., control information you can rule in today's environment. Information is controlled not through banning alternate views—the blogosphere can present all kinds of contrary information, but by endlessly repeating propaganda so that it becomes truth. This happened, in its most obvious way, by endlessly associating Saddam with Al-qaeda and WMDs even though most experts knew very well there was no truth to either claim. But because the propaganda organs endlessly repeated it became "true".
Most people identify themselves tribally. For example, the gist of Thomas Frank's book What's the Matter with Kansas is that people are willing to forgo all kinds of personal advantages in favor of tribal identification. Conservatives often oppose environmentalists because of tribal reasons not practical and reasonable reasons—i.e. Environmentalists are "kooks" and not "like us" therefore whatever their position is put me in the opposite corner. The same is true for leftists but less so. With that in mind the best thing to do is to gather in the tribe and support each other rather than try to convince others to join our tribe (it won't happen to any large degree anyway). What would encourage others to join our tribe is to show others that we are strong, vibrant, happy and prosperous (without excesses of the rich).
The way to create this gathering of the tribe or tribes (we cannot fit easily into one mold) we need to create a cooperative movement. I see no other political opening for the left given current conditions.
Corporations are at a competitive advantage over individuals and communities as currently constituted. So in order to play on a level field we need to organize ourselves into some cooperative-style corporations (with all the legal protections therein) with a view towards providing education, employment, housing, health-care and cooperative buying clubs and so on for members. By having real "boots-on-the-ground" political power we can influence policy in the same way as corporations and dedicated groups like AIPAC or Cuban-Americans and many other groups that organize for common goals can. Moveon is a step in the right direction but lacks the ability to insure consistent loyalty to itself since it does not really tie us together economically and culturally. A cooperative system like I envision would instantly be able to boycott companies and organizations that threaten our well-being. We could instantly carry out political threats to withhold political funding to candidates and so on.
The reason why my suggestion may not fly and hasn't flown is because we are still in thrall to the notion that in a liberal-democracy we are a government of laws and democratic institutions. I suggest that this is not true. I suggest that we cannot avoid giving up our liberties. I suggest that it is better to give up some liberties to a larger organization of like-minded people now than to be forced into giving up our liberties to the emerging security-state that bears no resemblance to what the Founders envisioned—that, in my view, is a dream that lies in the past and is, essentially, dead. Within a truly democratic/cooperative institution that represents our interests we have a good deal of say in what happens (if organized carefully) and have to give up some of our long list of consumer "choices". We might have to settle for a collective IT system—a committee might judge what brand of lawn-care equipment to buy or impose building restrictions. This can all be worked out—but we have to follow this path because we are coming into a period of history which will be both Imperial and/or neo-feudal. As it stands political society cannot guarantee our well-being or our liberties or that our system of law will be followed faithfully. Everyone knows by now that there is one system of law for the rich and well-connected and another for the rest of us and that is simply not going to change no matter who the next President is—not because the next President will be as profoundly nasty as this one but that he/she will simply not have the practical power to significantly change the general cultural and political trend, or the trend of history. There simply aren't enough of us who have an interest in using reason to judge practical or political matters. However we cut it don't represent more than 15-20% of the people of the U.S. If we organized and used our creativity that 15-20% could dominate politics for a generation.