The primary is almost over, Clinton's favored in the remaining vote, and she's won the popular vote 56-42 so far. Where are these national numbers coming from? Unless a bunch of Clinton voters had buyer's remorse, we have the actual numbers that this poll is trying to approximate.
Don't be a Hillary hack, you silly unskewer. Everyone knows that polls > election resuts. Romney should've filed a lawsuit to overturn the results because Gallup and Rasmussen showed him winning.
In all seriousness, the reason for this is because junky Reuters includes ALL independents, including right wing ones that would never vote in a Democratic primary, in the question.