Charlie asked a while back, “Can anyone explain–or point to an article where this is discussed–why Clinton was on the MI ballot, but not Obama?” Mr. Super has an answer, in “Florida & Michigan Timeline – How we got here.” From the Politico last fall,

“We will honor the pledge and not campaign or spend money in any state that is not in compliance with the DNC calendar, but it is not necessary to take the steps necessary to remove Senator Clinton’s name from the ballot,” said her communications director, Howard Wolfson.

Basically, Obama and Edwards appear to have interpreted their pledges not to campaign in states holding unsanctioned early primaries as meaning they should get off the Michigan ballot; they couldn’t get off the Florida ballot because it seems a candidate has to be on the primary ballot to be on the general ballot in Florida. Clinton (and Dodd) appear to have decided their pledge did not bind them to get off the Michigan ballot. When asked about this decision, Clinton said,

“It’s clear, this election they’re having is not going to count for anything…. But I just personally did not want to set up a situation where the Republicans are going to be campaigning between now and whenever, and then after the nomination, we have to go in and repair the damage to be ready to win Michigan in 2008.”

I am not sure exactly what this means; perhaps that Clinton assumed she would be the nominee, and wanted Michigan’s Democratic delegates in her corner, rather than left in some sort of purgatory, while the state’s Republican delegates endured no such snub.