The thing is if Democrats win the White House, they are going to need to pick up at least 10-15 House seats if they want to have some insurance against the 2010 midterms when they are almost certain to lose seats in the House.  My advice for Democrats would be to try to win around 15 more House seats in 2008 and then start working heavily the minute Hillary Clinton is inaugurated to protect those seats for 2010.  This is what Carter did for 1978 and Democrats lost a minimum number of seats.  Bill Clinton failed to do this in 1994 and he lost 54 seats for it.  

2010 may very well be a bad election for the Dems, especially in state races, which sucks because of redistricting.

They are going to be defending a few open Gubernatorial seats they probably don't have a good shot at holding on to (Kansas, Oklahoma, Wyoming), plus a few that will be difficult if the Democratic Party is unpopular (Arizona, New Mexico, Pennsylvania, Maine, Michigan, Wisconsin, Tennessee, Oregon) and some incumbents who may or may not be vulnerable (New York, Ohio, New Hampshire, Massachusetts, Arkansas, Maryland, Colorado.) A bad year for the Dems could hurt chances at open blue seats (Hawaii, California, Minnesota, Connecticut, Rhode Island) and against GOP incumbents (Florida, Vermont)

Senate races could be impacted by the chances of popular GOP governors running for seats in Hawaii, California, Connecticut, and North Dakota. As for the House, depending on how districts vote in 2008, we may be able to tell how many Democratic-held districts or future Democratic districts could change hands in one election cycle. A gain of 10+ seats may save the Democrats from any national landslide. I don't forsee a 1994 style seat loss for either party in the near future. Whether or not Corzine survives in 2009 and if Democrats can find someone to successfully hold onto Tim Kaine's seat in Virginia will also provide clues.

Let's first get through 2008.

Governorships:  Democrats should be able to hold New Mexico, Pennsylvania, Maine, Michigan, Wisconsin, and Oregon.  They are all basically Democratic states.  Most of our incumbents should be in solid shape.  We will probably lose Kansas, Oklahoma, and Wyoming, but don't see how on earth we don't pick up all of the open blue seats you mentioned save Minnesota.  Arizona and Tennessee both depend on who is in the White House and how popular they are.  My guess is that Democrats hold about even in governorships in 2010.

The good thing about the Senate races in 2010 is that Republicans already picked off pretty much every seat they had a chance at in 2004.  The only one that we could be in trouble in is North Dakota.  

We need to prepare long and hard in the House.  We need to pick up at least 10 seats in 2008 to have protection against 2010.  

to protect state legislative gains.  This is what killed us for the 2002 redistricting.  Democrats lost about 500 state legislative seats in 1994 and failed to win any back until 2004.  This allowed Republicans to kill Democrats in redistricting.  

at the GOP nomination.

I'd even give McCain a 10 percent shot at the nomination. Giving Rudy a 45 percent chance at winning is crazy.

is nonsense, don't the Republicans already have 17 open seats? That will probably be at least 25 by election time, maybe even 30.

And the political climate has not improved for them, it has continued to get worse. I see the Dems picking up a minimum of 10, probably closer to 20.

Yes, it feels like Dems will pick up about 15 House seats.  

But here is my question:  Isn't it reasonable, all other things being equal, to expect a steady generic ballot ("Would you vote for a D or an R for Congress next election?") advantage to result in the same make up of the House rather than the same change in the House?  Thus, if the generic ballot advantage, currently about 10%, is holding steady from 2006 one would expect a small change in the make-up of the House.

And here is an attempt at an answer: all other things are not equal.  The Presidential election is likely to ring out millions of new voters; young voters and occasional voters, and that will favor Dems.  (In Illinois, there is a likely pick up of 1-3 seats on that basis alone.  then when we add the Republican retirements and the small legislative victories in the Democratic controlled House, pick-ups north of 15 seems correct.

How are we doing on our way to 60 seats?

Senate seats which I'd offer better than 60-40 chance of picking up: New Hampshire, Virginia, Colorado, New Mexico.  Seats which now rate more or less 50-50 pickup are Minnesota, Oregon.  Seats which are in play, with good Dem challengers against a weak Repug incumbents: Alaska, Kentucky.  We've got a good challenger in Maine but lag well behind now.  So, how do we get to 60?  I feel that will depend on the advantage of our national ticket.

We will likely win 3-8 Senate seats and 10-20 House seats.

I'm hoping we can pick up 30 House seats, including 5 here in Ohio. With a continuing quagmire in Iraq, gas prices high, a recession on the horizon, and blatant Republican corruption and cronyism, the environment for Republicans is miserable. All the Republican Presidential candidates are promising 4 more years of this crap. Healthcare should be a big issue in 2008 and the Republicans have nothing useful to offer. And Republicans are having a hard time raising funds. Lots of Republicans have already announced their retirements and I expect many more.

If Democrats win the two special elections on December 11, it should encourage even more Republican retirements. Democrats running in these seats: liberal Robin Weirauch in OH-5 (ActBlue site) and centrist Philip Forgit in VA-01 (ActBlue page).

I would put both a Hillary nomination and a Democratic victory at about 60% probability.

I have no idea who the GOP are going to nominate. Maybe Romney has a tiny edge but he is screwed if Huckabee continues to surge in Iowa.

Dems should win 10-15 seats in the House while losing 3-5 (Lampson, Mahoney, Carney, Boyda and Marshall most at risk).

Dems to take 5-7 in the Senate (in order of probability - VA, NM, NH, CO, MN, OR, KY, AK, ME, NC, TX, OK, TN, GA, KS, SC) with no loses.

Jonathan - I think you are underestimating the Dems chances in 2008.  I think you are about right on the Dems chances of winning the presidency, but way low on the number of House and Senate seats that the Dems are going to win.  My guess is that the Dems are going to win 7-8 Senate seats.  They are going to win VA, NH, NM, and CO fairly easily, The Repubs are in serious trouble in KY and AK (Bush approval around 40, senator approval ratings below 50), and the Dems are going to at least split OR and MN (Bush approval below 40 and senator approval ratings just below 50).  That doesn't even include NC (Bush approval around 40, senator approval rating below 50), or longer shots like ME, TX, ID, NE, or OK.  If the seats fall like they did in 2006, or even 2002 to Republicans, then the Dems are going to win many more seats than are currently predicted.

The House is the same way.  The RCCC is a complete mess and worse than broke.  RCCC candidate recruitment is nonexistent, and the Dems are riding a wave, with lots of money and good candidates.  Lots of Repubs are retiring, and the Dems maintain a big advantage in the generic ballot.  Plan on the Dems winning 22-27 seats.

The key here is that the rating services are always lagging indicators.  They do well in relatively neutral years, but very poorly in wave years, like we saw in 2006.  They did poorly in 2006 - why should we believe them now?