Lotsa reasons why the Left is different from the Tea Party, but this is the big one.
… what made the tea party successful, according to Theda Skocpol, a Harvard professor whose field studies of the tea party movement became a 2011 book, was a particular climate on the political right. “We thought of the tea party as a set of several intersecting forces that were leveraging each other and helping to build each other’s clout to change and use the Republican Party,” she said. Self-organizing grass-roots groups, top-down professional advocacy and money groups, such as FreedomWorks and Americans for Prosperity, along with right-wing media, swirled together to make the movement a success, according to Skocpol. It remains to be seen if the climate on the left will prove to be hospitable for the growth of a similarly effective movement.…
In addition, the right had been pushing ideology in an organized way for decades.
The Left lacks these resources. Occupy was a self-organizing grass-roots group, but there is no professional advocacy, no big money in the background (regardless of all the hype about Soros), and no left-wing media to speak of. Moreover, there has been no organized push for leftist ideology in the US comparable to that on the right for many decades