He surveyed 1,200 likely voters in the 60 most competitive Democrat-held districts and ten most competitive Republican-held districts. In Tier 1 (the 30 most vulnerable Democratic districts), Democrats trailed by 48 to 39 overall. In Tier 2 (the 30 next most vulnerable districts), they trailed by 47 to 45. And in the contestable Republican districts, they trailed 53 to 39.
Here's a money quote from Galston:
Earth to House Democrats: It’s time to push the panic button. But don’t take my word for it; consider the evidence...It’s too late to enact legislation that will actually affect the economy’s performance between now and November, but it may not be too late for Democrats to better align their agenda with the public’s economic concerns. And they could get lucky: The four remaining employment reports between now and the election might show accelerating job creation in the private sector and a more rapid decline in unemployment than we have seen thus far. That would give embattled incumbents the chance to argue—more credibly than they can now—that we’re on the right track and shouldn’t turn back.
From what I've seen in the past year, I think that a 70 seat gain in the House is, perhaps, conservative...