a theory on Dems backing DLC & Blue Dogs who are useless for progressive legislation

The obvious reason is simply corruption: get the money from the rich now in campaign contributions and as jobs from them after politicians leave office as lobbyists, CEO's, and highly paid, do-nothing board members. Good policy and progressive groups don't have the money to outbid that.

But whether through strategery or simply a side effect of that corruption, holding onto majorities even when it is incapable of the real change needed serves a long term positive for our democracy:

Republicans are literally dying out. It is the party primarily of old, white, racists and zenophobes who think they will someday win the lottery and join the real Republicans, the very, very wealthy. As America becomes browner and increasingly simply younger (kids aren't afraid of gays so much) those groups are shrinking to a minority that cannot seduce enough of us to form a majority.

Republicans know they are dying out which is why, since the 90s, they have relied on increasingly thuggish methods to get and hold onto power. Hence chasing black people away from the polls, and even ever more ham-handed supreme court decisions like Bush v Gore and Citizens United.

Their only hope to hold onto power is to break democracy while they are in the driver's seat and use brute force to keep it thereafter.

That's probably why Tea Party candidates seem even crazier than previous Republican extremists: it's possible that some right wing pols actually believed in the Democratic process and were reluctant to destroy it when they had a chance. Tea Baggers like Christine O'Donnel or Sharon Angle would not share that reluctance anymore than your dog would be reluctant to eat the Constitution if you spilled pot roast gravy on it. They simply don't know what they are destroying.

The Democrats face a couple of problems in overcoming this: one is the Supreme Court increasingly stacking the deck against them as they did with those two previously mentioned decisions, and the other is the wealthy's stranglehold on the media and really all channels of communication, even the internet, which they would choke if they were truly threatened.

You have freedom of speech in America only so long as no one takes you seriously or no one is listening.

If the Democrats take any bold action, it could succeed and build massive public support that outweighs the inherent advantages the rich have. But if it isn't big enough, the consequences could be disastrous.

If Pelosi and Reid had done what we wanted from 2006 on and the public support had not been enough to overcome the inherent advantage of the rich, McCain or Palin would have picked replacements for two of the left wing Supreme Court justices, which would give the right an inherent advantage long after they could no longer win elections.

So if the Democrats continue to throw us bones here and there when it doesn't offend the rich and carry water for them on big issues, they can retain the levers of power long enough for the right to die out before they can end our democracy.

California is much further down this road. There is essentially no way the Republicans can retake our legislature and they are left with only obstructionism because of a quirk in our constitution requiring a 2/3 vote to pass a budget or raise taxes. Eventually, they won't even have that third left.

Democrats in DC could end the GOP obstruction in the Senate by changing the rules, but what would the backlash be from the rich? Would there be enough public support to weather it? So whether by design or default, they are waiting for the GOP to die.

Politics is like a very long game of chess, and sometimes we and even politicians only see a move or two ahead. The GOP base doesn't even see that far. They just see the color of the piece and stomp on the board.