Cook's 2010 Forecasts

The Cook Political Report reports their educated guesses for November's election results. Big picture:
How many other wavering House -- or Senate -- Democrats will look at the past five weeks and decide that spending the rest of this year as a lame duck is more attractive than spending a horrific year fundraising, scarfing down fast food, and shaking hands -- all the while facing the very real possibility of losing in the end? When their party starts singing endless choruses of "This is going to be a lousy year," lawmakers can easily find themselves humming along.

Come November, Senate Democrats' 60-vote supermajority is toast. It is difficult, if not impossible, to see how Democrats could lose the Senate this year. But they have a 50-50 chance of ending up with fewer than 55 seats in the next Congress.

As for the House, we at The Cook Political Report are still forecasting that Democrats will lose only 20 to 30 seats. Another half-dozen or more retirements in tough districts, however, perhaps combined with another party switch or two, would reduce Democrats' chances of holding the House to only an even-money bet. We rate 217 seats either "Solid Democratic" or "Likely Democratic," meaning that the GOP would have to win every single race now thought to be competitive to reach 218, the barest possible majority. But if Democrats suffer much more erosion in their "Solid" and "Likely" columns, control of the House will suddenly be up for grabs.
I think that these are reasonable assumptions. I think that it's likely a sure bet that the Dems will lose seats and the Republicans will gain. I don't think we'll see a paradigm shift in power (which is a good thing for the GOP), but the Democrats' will have an even tougher row-to-hoe come 2011.