E. J. Dionne, this morning:

Worse from the Democrats’ viewpoint, Dorgan’s move fed exactly the story line that Republicans have been pushing hard: Combined with the retirements of Gov. Bill Ritter in Colorado and of a number of incumbent House Democrats, Dorgan’s decision looked to be part of a mass flight of vulnerable members of President Obama’s party from a grim political battlefield.

At some point, this stops being “a storyline that Republicans have been pushing” and starts being an obvious fact. Every one of the Democrats who dropped out Tuesday and Wednesday morning insisted they could have won their races in November 2010. Horsepuckey. You don’t spend a year working hard, preparing to achieve a goal, and then suddenly drop it because you “haven’t found the right balance” (Ritter) or you’ve suddenly realized “there are moments for each elected public servant to step aside and let someone else step up” (Dodd) or “I have other interests and I have other things I would like to pursue outside of public life” (Dorgan).

John Cherry came closest to acknowledging his campaign’s troubles, attributing his withdrawal to an inability to “secure enough money to make my candidacy fully viable.”

If all of these guys had been up 20 percentage points on their opponents, they would all still be in the races.