There has always been a tendency in American politics for the fortunes of political parties to ebb and flow. As the tide for one party comes in, it recedes for the other. During the closing days of the 1998 midterm election, and even more so just after the impeachment trial of President Clinton, the tide was definitely running in favor of the Democrats.

Republicans had every reason to view the 2000 congressional elections with trepidation. But now the Democratic advantage is gone, and the shifting tide is at a point where neither party possesses any real advantage. The combination of the conflict in Yugoslavia and polls that show the top two Republican presidential contenders holding large leads over Vice President Al Gore means that it's now the Democrats who seem more worried about 2000. Certainly Democrats can reassure themselves with the knowledge that the November 2000 elections are more than 18 months away, but the shifting tide is troubling nonetheless.

As with most shifts like this, there are several distinct causes. First and foremost, Republicans began the year bathed in

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