Let's see...
According to the Kos numbers, Obama has 1,964 delegates sewn up right now.
We have Puerto Rico, Montana, and South Dakota yet to do, and we're still fretting over Michigan and Florida.
Let's consider a disastrous scenario...
This will be rough, because I'll use Slate's Delegate Calculator, which is only a crude estimate. For that reason, let's tilt everything Hillary's way.
Let's give her a 20 point win in Puerto Rico, and 10 points each in Montana and South Dakota. In addition, let's seat FL and MI at full strength. In fact, let's give Clinton 10 points in Florida and 20 points in Michigan. Here's the delegate breakdown:
Clinton:
Puerto Rico 33
South Dakota 9
Montana 8
Florida 102
Michigan 77
--
Prospective 229
Done 1,780
_______________
Total 2,009
.
Obama:
Puerto Rico 22
South Dakota 7
Montana 7
Florida 83
Michigan 51
--
Prospective 170
Done 1,964
_______________
Total 2,134
Since we're including Florida and Michigan, we've moved the goalposts from 2,025 for the nomination to 2,209. This leaves Obama 75 delegates short of the nomination.
There are 210 Supers unaccounted, so, in this absurd scenario, Obama would need 36% of the remaining Super Delegates to capture the nomination.
36%.
It's likely that I've made some errors in this math, because I don't know how the Supers from FL and MI play into this, and so forth, but I think this crude calculation captures the hopelessness of Clinton's situation.
She hasn't "earned the right" to the VP slot; she hasn't "proven her electability"; she hasn't done anything but lose.
This is why Obama has stopped talking about Clinton.
If we had a lick of sense, we'd follow suit.