The sample is WAY too old. 44% over 65 for the Dem side. 11% under 34. I imagine the polls showing this 10-15 points is right.
Pennsylvania's electorate has always skewed older. This particular poll might skew that a bit more, but a 10 point race would be 55% - 45% and a 15 point race would be 57% - 42%.
Hillary getting 58% is optimistic, but entirely within reach.
2008 Democratic primary age breakdowns:
12% under 30
19% 30-44
37% 45-59
33% 60+
A plurality of that electorate voted for Bill twice and Hillary in 2008. I think a 27 point win is incredibly unrealistic but 12-15 points is certainly in the ballpark