Some will try to minimize the importance of any Republican gains tonight by saying the Democrats were bound to lose. Some will even say Democrats had a baked-in loss of 45 or more seats, which implies they had no hope of keeping the House at all, no matter what policy aims they worked to implement. The problem is, that's nonsense.
Cutting to the chase: while the 2008 electorate was never, ever going to be duplicated in this or any midterm election's turnout, previous midterm elections showed that the Democrats were capable of keeping the House, and therefore capable of keeping midterm losses down to reasonable figures. Here's how.
Most notably, to see a midterm election that favored the Democrats we can look back to 2006. With the same House districts the Democrats were capable of winning a 233 D-202 R House majority. For comparison, my final Swingometer projection says 235 R-200 D, and my own private projection says 248 R-187 D.
One objection to that is of course that the "national mood" is different when a Democrat is in the White House. Fine, let's look back at the last midterm with a Democrat in the White House, 1998. In that year, Democrats turned what is usually a disaster of a second midterm election into a gain from the previous, winning 5 more seats from 1996 to close the Republican majority to a small 223 R-211 D (plus Bernie Sanders) total. They are capable of bucking history if they connect with the American people as Bill Clinton did.
But Barack Obama has not, and that is why election after election this year will turn on the President, and Democrats will lose elections as a result. Even Russ Feingold is having that problem. Joe Manchin tried to avoid it by literally aiming a gun at and shooting a core element of his party's and his party's President's domestic agenda.
The Democrats did not have to lose this year, but if they had difficulty it's because Barack Obama was too busy looking down on the bitter clingers to reach out to Americans, gain their trust, and convince them to support his party in this year's elections. This election is on his head.