Negative Campaigning
One reason why Democrats aren't likely to experience a 1994-style wave of congressional takeovers (though I'll keep my fingers crossed) is either the disinclination, or inability to do this:

Republicans are planning to spend the vast majority of their sizable financial war chest over the final 60 days of the campaign attacking Democratic House and Senate candidates over personal issues and local controversies, GOP officials said.

The National Republican Congressional Committee, which this year dispatched a half-dozen operatives to comb through tax, court and other records looking for damaging information on Democratic candidates, plans to spend more than 90 percent of its $50 million-plus advertising budget on what officials described as negative ads.

I've already seen this here--the first negative ads against Harold Ford run by the Republican National Committee. It's classic stuff: ominous music, the voice that sounds right out of a horror movie preview narration, and charges that Ford is essentially uninterested in keeping Americans safe.

Wouldn't it be nice if for once this didn't work? Backfired even? If Americans were finally so sick of seeing the party in power run the country into the ground in favor of corporate interests at home and a domineering, simple-minded and deadly bravado abroad? But is there any reason to believe that the most massive negative campaign in US history won't work?