If only Hillary Clinton was a Republican, she would have already locked up the nomination.
I had heard that if the Democrats used the delegate-selection system that Republicans use, then Clinton would be ahead in delegates, but I couldn't find any numbers to tell me exactly by how much. So I charted the delegates won by Obama and Clinton on a primary by primary basis in real life and as if they were apportioned using whichever rules the GOP was using in that contest. In most states, the Republicans use winner-take-all or winner-take-most, but there are a few (e.g. Iowa, North Carolina) where the splits are more proportional to the popular vote. I had to guess on some contests (particularly the winner-take-almost-all primaries), but I have come up with (I think) a fairly reasonable estimate of the difference between the number of pledged delegates Clinton would have and the number of pledged delegates Obama would have if the Democrats copied the Republican's rules, shown below.
Hillary Clinton is down by around 162 pledged delegates in real life, but she's up by around 429 pledged delegates in the GOP-style fantasy situation. Her chances are slim at best, and people are calling for her to quit campaigning and step aside at a deficit of 162. But if Obama had a deficit of more than 2.5 times that, he'd already have had to quit and yield to the mathematical certainty of a Clinton nomination.
So why fuck around with delegates, respective political parties? This is supposed to be a government where people directly elect representatives. Yet even the general election we have the electoral college, not the people, deciding who the next commander-in-chief will be, and sometimes the result can be very different. Why should the political parties mimic this inane system? Since a 600-delegate swing exists when different rules are in play, why must we mess around with unnecessary layers of representative amalgamation that serve only to distort the will of the people?