Now, to look at the match-ups. (I am only including Clinton and Sanders since Biden has not declared)
Next, I have broken down the undecideds for each of the above match-ups. The percentages represent the undecided share of that party calculated as a percentage of the total sample.
Another weird thing in this poll: Among Democrats and Democrat leaners: 52% consider themselves moderate or Conservative. Among Republicans and Republican leaners: 34% consider themselves Moderate or Liberal. So it appears that their sample seems to favor moderate Democrats over hard core democrats and hard core Republicans over Moderate Republicans.
Now lets look at how the undecided voters break down between the two sexes.
The point in all of this? Well that is two-fold. For one, this poll undersamples minorities, Democrats and Women. These are all Democratic leaning voting blocks. Second, among the Republican leaning sample that we have: the strength of Clinton is underrepresented even among this electorate due to the layout of the undecideds. Overall? Clinton is doing better than this poll would make you think.