Somebody: I find most of this editorial disingenuous. In fact, from reading Democratic-oriented and progressive blogs it's quite apparent that most on the center-left who've been critical of Obama have simultaneously responded to the racist attacks against the President.
Firedoglake, for example, the website founded by Obama critic Jane Hamsher, is at once filled with progressive critiques of the White House and Congressional Democrats *and* denunciations of Birthers and Tea Party racists.
Also, the impression I get from the editorial is that progressives are all white, or anyway do not significantly overlap with the Black Americans who are "murmuring" about racist Republicans. It's 2011. The U.S. is way too diverse to continue with the same tired white liberal stereotype of 60's. To state the obvious, the progressive community includes whites, blacks, liberals, Hispanics, Asians, and Native Americans.