Perriello was always going to be vulnerable this cycle, but he didn't do himself any favours by voting for the Healt Care Act.
Walt Minnick seems to be in far better shape for example, even though he represents a far more Conservative district than Perriello.
Perriello is unusual in that he votes in what he believes in and what is best for the country, even if it doesn't poll well in his district. So he is probably gone, but having accomplished something, at least.
Minnick won because he was widely respected by Republicans and drew crazy challengers. Perriello never had the first advantage and won't have the second this year.
He's there to represent the district, so I'd say polls should be pretty important.
