The fight over the Cromnibus has elevated Warren’s profile, and you will soon be hearing a lot more about her from the activist left and from mainstream media journalists (partially overlapping categories). So it is a good time to keep in mind that Warren’s natural base of upper-middle-class white liberals is large and wealthy enough to raise money and make noise, but lacks the numbers to seriously threaten Hillary Clinton for the Democratic nomination. Jim Webb’s natural base of Democratic-leaning Jacksonians (whose views don’t map all that well on of left-right axis) are also too few to actually get the nomination.

Clinton’s vulnerability is that she has tried to position herself as slightly more hawkish and pro-business than Obama. Warren is positioning herself to Obama’s left. The key to beating Clinton is combining that minority of Democratic voters who think of themselves as left-of-Obama with voters who strongly approve of Obama and don’t appreciate the thought of a candidate who is tighter with Wall Street and quicker to commit US troops than the current president. Warren and Webb could bring Clinton’s numbers down by attacking her, but I don’t see how either of them has a path to the nomination. I still think that the much-mocked Biden is best positioned to put together a coalition of strong Obama supporters and dissent middle-class liberals that could challenge Clinton.