From Chris Cillizza at the Washington Post:

Combine the similarities between 1994 and 2010 on the generic ballot and presidential approval with a clear intensity gap between the Republican base (fired up to vote) and the Democratic base (less so), and Democratic strategists are worried that they are watching history repeat itself.
“Our losses occurred because Republican turnout was massive,” said one senior party strategist deeply involved in the 1994 campaign. “The right was motivated in 1994, and while it would have seemed impossible to me then, it feels like the Republicans are much more motivated to participate in this election” than they were then.
Although few savvy Democratic strategists debate the difficulty of the national political environment, they do note that there are two important differences between the 1994 election and this one.
The first is the relative weakness of the Republican brand. In 1994, Republicans had been out of power in the House for four decades, and most voters had a limited sense of what aGOP House would be like. In 2010, the American public has fired Republicans — in the House, Senate and White House — twice in the past four years. And, in a recent NBC/Wall Street Journal survey, the GOP had its lowest favorability ratings ever. (We repeat: ever.)
Second, Democrats understand the building frustration and desire for change in a way that the party simply didn’t get 16 years ago. “The one advantage Democrats have is early-warning radar that we are facing a tough environment, and many of our incumbents have geared up their campaigns much earlier than in 1994,” said Fred Yang, a leading Democratic pollster. “The possible wave may be too big for any campaign, but we’re going to be ready this time and run harder and more aggressive campaigns.”

I wonder if “we” includes the president, who appears to be politically tone deaf. If a Republican runs against him and the lame-duck session to start with, that’s a tough association for any Democrat.