Here’s the question nobody on the left wants to ask: are progressive Democrats poised to go the way of Republican Tea Partiers? That is, exiled to the margins and ignored as the party's centrists seek to regain power?The front pages of America’s most influential newspapers are touting that the Republican Party’s biggest lesson this year was they realized they had to “crush the enemy,” asThe Times put it, “not Democrats but the rebels within their own party.” And so they did.Is that what is coming in Democratic Party circles?