At the risk of beating a dead horse, I took Northern Sky's excellent diary today noting that after Pennsylvania, Clinton now needs 71% of the remaining vote to catch Obama in pledged delegates. I decided to expand upon this analysis and add in currently pledged superdelegates and split the remaining unpledged superdelegates evenly to see how much Clinton will need to overcome in order to catch Obama.
Using The Green Papers as my source, I start with the following allocation of pledged delegates as of today:
Obama 1490
Clinton 1337
Remaining 408
Next, I took the remaining 9 contests, broke them down into at-large and congressional district races to determine delegate allocations based on popular vote, and assumed an even popular vote across all remaining contests.
The first question was to determine what percentage of the vote Clinton would need to overcome Obama in pledged delegates only. My answer differed ever so slightly from Northern Sky's, perhaps due to a different starting point for pledged delegates. I found that at exactly 70% of the popular vote, the 408 pledged delegates yet to be voted on split 289 for Clinton and 119 for Obama, yielding:
Obama 1609
Clinton 1626
So she would have to have a 40% spread (70/30) from here on out - possible in West Virginia and Kentucky, but nowhere else.
Fine, what about the superdelegates? The Green Papers shows the breakdown as follows:
Clinton 253
Obama 230
If we give Clinton the benefit of this 23 SD lead (assuming the remaining SDs and the 18 Edwards delegates split evenly), then her chances improve ever so slightly, requiring a mere 64.3% of the vote to Obama's 35.7%, or a spread of 28.6%
Of course, Obama has been picking up SDs since Super Tuesday at a clip exceeding 4 to 1. Below are the popular vote total required for Obama and Hillary to claim victory based upon remaining unpledged SD breakdowns of 20/80, 40/60, 50/50, 60/40, and 80/20:
O - 20% C - 80% remaining SDs
Obama 58.3% popular vote
Clinton 41.7%
O - 40% C - 60% remaining SDs
Obama 41.7% popular vote
Clinton 58.3%
O - 50% C - 50% remaining SDs
Obama 35.7% popular vote
Clinton 64.3%
O - 60% C - 40% remaining SDs
Obama 25.0% popular vote
Clinton 75.0%
O - 80% C - 20% remaining SDs (recent trend)
Obama 15.0% popular vote
Clinton 85.0% (UPDATED - forgot about that 15% minimum to get delegates)
The chances of any of this happening for Clinton are so remote that it is hard to believe that anyone thinks it is possible.