Trump won PA's 18th by 20 points.
The election just held seems to be a win for the Dem's by about 500 votes; this in a race that was "safe" for the R's.

http://www.bbc.com/news/world-us-canada-43390652

One off or possible tsunami?
It seems a lot will hinge on turnout. Trump does not appear to be a positive factor, even for incumbent Republicans.

https://fivethirtyeight.com/features...nto-a-tsunami/

Could be a very interesting mid-term season.