Dem house Majority unlikely my ass

[Mr.Phips]

Lot of Republican-held marginal seats that were shored up this year.

The only marginal Republican seats that were put out of reach for Democrats are NC-02, TN-08, OH-01, OH-15, IN-09, NJ-07, and maybe PA-03.  The rest are still very winnable for Democrats. 

[Mr.Phips]

Gerrymandering certainly helps the Republicans.

There have been some solid wins in past that did not result in that party winning the House.
1956, 1972, 1984, and 1996 come to mind.

1956, 1972, and 1984 were a different time period where ticket splitting was much less common.  1996 was different as Clinton got only 49% and the overwhelming majority of Perot's voters went Republican downballot.  If you look carefully, in most competitive races, Clinton's percentage closely tracked the House or Senate Democrats' percentage.  I suspect that will happen again in 2012. 

[Mr.Phips]

Lot of Republican-held marginal seats that were shored up this year.

I suspect the Dems will need to win the popular vote in the House by about a 53%-47% margin for the odds to go their way that they will take control over the House. The tipping point is about a 2.75% GOP PVI CD, and in addition to that, you now have the Pub incumbency factor, which is typically worth about 3 more points if the incumbent is reasonably competent. It is going to be a very uphill climb for the Dems. The Pubs have been rather systematically building a firewall of some formidability in a coordinated national effort. It was a top priority of the RNC, and they had a whole team put together to coordinate with the Pub state legislatures.

I think Democrats winning the House popular vote 51%-48% would be enough to swing it.  The average district only moved from R+1.8% to R+2.1%. 

[Mr.Phips]

Lot of Republican-held marginal seats that were shored up this year.

The only marginal Republican seats that were put out of reach for Democrats are NC-02, TN-08, OH-01, OH-15, IN-09, NJ-07, and maybe PA-03.  The rest are still very winnable for Democrats. 

I'd add SC-05 to that list of marginal seats that were made safe.  Without redistricting, Mulvaney might have been a vulnerable freshman, if he faced a quality Democratic opponent (which sadly are hard to come by in this state as one-party rule is never good, no matter which party rules).  Not that the 2010 elections changed much here.  Possibly the Republicans would have made the 5th a bit more Republican to make certain they would defeat Spratt it he had survived for one last term.  But a 6-1 redistricting plan was a foregone conclusion.

It was only made about two points more Republican.  Vincent Shaheen would have made it a real race against Mulvaney.