Here's some interesting context to the behind-the-scenes battle that's underway between Hillary and Obama for the support of super-delegates. It turns out that the super-delegates have received campaign contributions from both sides, though its unclear whether this money has had any impact on any decisions they've made.
The Center for Responsive Politics has a new study out which finds that the two have donated a total of more than $890,000 to those super-delegates who are elected officials in the past three years. Who's donated more? Obama has, by far.
According to the study, Obama's PAC and campaign committe have given out $694,000 to such superdelegates. Some 40% of the supers who support Obama received cash from him, the study finds.
Hillary's PAC and campaign committee, meanwhile, have donated only $195,000 to supers, less than a third of what Obama has, and only 12% of supers supporting her have received her money.
So, Obama's financial apparatus appears to have given out far more cash to the supers than Hillary's has -- though again, it's not possible to assert at all conclusively that there's a direct link between donations and the decisions by the SDs.
Late Update: I should have made it clear that these numbers refer to donations in the 2006 and 2008 cycles, so many of these could have been ordinary contributions to fellow Democrats before either was running for President. I've revised the above accordingly.