Unfortunately, 538 does not currently have a House Congressional projection. I have never followed how closely the generic D and R congressional polls translate to results on election day.
This electionprojection.com web site seems to be predicting the Republicans will continue to hold a painful +50 (242R-193D) seat led:
electionprojection.com
Here is some rough sketch data I collected from RealClearPolitics, showing the aggreivate generic congressional poll margins and then what happened a few days later in the election (in percentage, not seats):
2004: AVG Polls=Tied Election=+3 R
2006: AVG Polls=+11 D Election=+8 D
2008: AVG Polls=+8 D Election=+9 D
2010: AVG Polls=+9 R Election=+7 R
2012: AVG Polls=Tied Election= ???
So it's 45.3R-45.0D right now with most polls tied. The exceptions are the CBS poll with the D’s up 2 points and Rasmussen with R’s up 3, which gives the average generic congressional poll edge to the Republicans by 0.3%.
Maybe I’m cherry picking, but it seems to me the key elections to look at are 2004 and 2008.
The 2004 polls were damn close to what they look like now both for generic congressional and incumbent/challenger for the Presidency. So from the 2004 data, I’m convincing myself we can edge ahead by 1 to 3 percentage points playing the incumbent party re-play of 2004. Then 2008 shows a bit of an Obama coattail thing.
Nancy meet gavel, again.....Poll after the fold.