Remember a lot of the Dems recent victories involved a great ground game. For that to happen you need lots of volunteers, and it’s hard to see where they’ll come from in 2010 even if Obama gets health care passed. There’s no Bush to be angry at anymore. The ground game is usually worth five points.

Another gigantic thing is that in off-years very few people vote. 36.8% turnout in 2006. There’s a large variation across states so in places with no Gubenatorial elections 25% is normal. That 36.8% is disproportionately extremist for the simple reason that extremists tend to be a lot more passionate about elections than moderates. Who do you thinks gonna show up if Obama can’t even get the pissant house program passed? That’s another five points.

I guarantee you CQ’s house ratings aren’t spotting the GOP the ten points they’d be likely to get if Obama walked away from health reform. They probably aren’t spotting the GOP the 5 points they’re almost certain to get without Obama’s ground game.

Here’s another take form CQ Politics

http://www.msnbc.msn.com/id/32172696/ns/politics-cq_politics/

The GOP would be energized by their success and vote in droves in the 2010 Congressional elections. Obama’s people would be very disappointing and stay home or vote Green. Why should I work my ass off to get Dems elected if those same DXems aren’t going to work their asses off to fix health care?

Obama himself would be in a somewhat better position than Clinton, as it’s virtually impossible to imagine a scenario that results in a GOP Senate (they’d have to lose all seats that aren’t Dem locks), and Obama already has a domestic policy achievement he can point to in 2012 (the stimulus).