Some of us thought that once Kavanaugh was confirmed, the Democrats might start actually doing better on the House level, as Democratic anger crystallized and Republican hyper-engagement subsided. Recent results suggest that may be happening--emphasis on the "may" because it's still too early to know for sure. But Ipsos' new release reports a +12 Democratic lead on the generic and CNN's has a +13 Democratic lead; these new releases have sent the Democrats' lead in the 538 rolling aggregate back over 8 points.
Nathaniel Rakich points out on 538 that it actually could be pretty important if the Democrats' does further widen over 8 points. He notes:
"[F]rom R+1 to D+8, Democrats’ gains in House seats [in our model] were fairly linear: They gain between one and four more seats with every point they pick up nationally. (That’s less than 1 percent of House seats for each 1 percentage point of the vote.) But when you go from a D+8 scenario to a D+9 scenario, Democrats pick up 10 additional seats, or more than 2 percent of House seats. Then, they gain an average of 7.1 seats (1.6 percent of the House) for every additional percentage point they pick up in the popular vote total (up until D+17); in other words, seat gain outstrips popular-vote gain."
If you feel like reading the entire article, there's an interesting explanation for D+8 as a cut point which makes good intuitive sense. Food for thought as we continue to track and ups and downs of the generic ballot.