This is, Chait argues, a much more potent weapon against the Brown campaign than anything else the pathetic Coakley campaign has yet managed to produce:
By showing Brown endorsing a fringe right-wing pet theory (explanation here), it's more evidence of the fact that Brown is anything but the good government, uniter-not-a-divider moderate he pretends to be. That's the fundamental lie of his campaign that Coakley has been seeking (unsuccessfully, thus far) to expose. And on a visceral level, to watch him chortling as he calls Obama illegitimate is just gross and offensive.
I'm inclined to agree. There's nothing about Coakley I find particularly exciting (and there are certain aspects of her record that are concerning), but she's clearly the right choice to succeed the late Senator Kennedy - especially since health care reform could be hanging in the balance.
That's why her meandering, incoherent, almost unbelievably inept performance has been so infuriating. At this moment, the stakes are just too high for her to screw up. And the last thing the Senate needs is another classless idiotic right-winger. There's a bastard in that video, all right - but it's not the president. Hopefully the good people of the Bay State will keep him out of the U.S. Senate.