It's the Latest Fad
Via ScrappleFace, Democrat Candidates Drop Out of Races Nationwide:

(2002-10-01) -- Following the example of Sen. Robert Torricelli, D-NJ, who halted his re-election campaign yesterday because he knew he couldn't win, dozens of fellow Democrats nationwide announced the end of their bids for office.

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The DNC is still scrambling to fill all the empty ballots with replacement candidates who have name recognition, a relatively clear criminal record and scant knowledge of the U.S.Constitution.

I'm sure they've considered it.