I just put up an Economist blog post about Gov. Bill Richardson, who is, to the apparent interest of nobody, doing really well in the Democratic primary polls. From a start in the low single digits Richardson has moved up to the low teens in Iowa and New Hampshire, inching pretty close to Obama in the Hawkeye state and past John Edwards in the Granite state. If you check out the averages on Pollster.com, Richardson is the only Democrat who's gained in every state: Obama has risen some and fallen some, Edwards has usually just fallen.
So if we assume that the polls are right and Richardson is slowly rising, what's the cause? He's less ambitious about tax hikes than the rest of the Democrats and he calls himself a "market-oriented Democrat," but that shouldn't necessarily excite Democrats. What's happening is that Richardson is polling disproportionately well among independents, and many of them—so, so done with George W. Bush and the GOP—need a candidate. Hillary's out of the question, Obama's increasingly unlikely, and Edwards is a drip, so they're looking at Richardson.
(The most recent numbers: In South Carolina only 1 percent of Democrats support Richardson, but 9 percent of independents do. In New Hampshire it's 6 percent of Democrats and, again, 9 percent of independents. In Iowa Richardson has an outright lead: 25 percent of independents.)