For Democrats demoralized by a succession of presidents who ran as progressives but then governed as centrists, Elizabeth Warren is the real deal. She brought the house down at Netroots Nation last July with lines like these: “A kid gets caught with a few ounces of pot and goes to jail. But a big bank launders drug money and no one gets arrested. … The game is rigged and it isn’t right.”
Kuttner speculates, probably rightly, that Warren will not challenge Clinton, but if for any reason Clinton does NOT run (which is always possible), she will find the impetus from the Democratic Wing of the Democratic Party (in Howard Dean's memorable phrase)... irresistable.