I'm not so sure about DE either - that "I'm not a witch" ad to kick off the campaign was a self-inflicted wound, and running cheaply produced ads with all of that cash was another. Even Joe Miller did a spoof of that "I'm not a witch" ad.
Buck and Angle lost due to personality issues, not due to ideology.
I agree that a solid conservative could have won in Colorado and Nevada. Whether the runners up in those primaries qualified as such I don’t know, but certainly those states aren’t California, the Pacific Northwest, or the Northeast where conservatives probably can’t win.
O’Donnell was just too easy for the Left to demonize.