The consensus seems to be that all eyes are on conservative Democrats now. Examples:
"This election is a referendum on the Bush administration's competence, not an ideological tide. The Democrats who are doing best - Casey in Pennsylvania, Ellsworth in Indiana, Heath Shuler in North Carolina - are moderate or even quite conservative." (David Brooks, New York Times)
"We could be seeing the creation of a more conservative House of Representatives than the one we have." – George F. Will, on ABC, via Rod Dreher, who interprets: "He means that the liberal-to-moderate Republicans are being knocked off, and the Dems that are winning House races are more conservative."
More TK, I'm sure.