The simple answer is because the Democrats told them not to.

For much of Tuesday, campaign workers exuded confidence after surveys of voters leaving the polls showed Mr. Kerry with an edge over Mr. Bush. But as the night wore on, the real results told a different story.

The critical moment came at 12:41 a.m. Wednesday, when, shortly after Florida had been painted red for Mr. Bush, Fox News declared that Ohio - and, very likely, the presidency - was in Republican hands.

Howard Wolfson, a strategist, burst into the "boiler room" in Washington where the brain trust was huddled and said, "we have 30 seconds" to stop the other networks from following suit.

The campaign's pollster, Mark Mellman, and the renowned organizer Michael Whouley quickly dialed ABC, CBS, CNN and NBC - and all but the last refrained from calling the race through the night. Then Mr. Wolfson banged out a simple, two-line statement expressing confidence that Mr. Kerry would win Ohio once the remaining ballots were counted.

"What was driving our decision making was the memory of how in 2000, by allowing Florida to go for Bush, a lot of momentum was blocked," said one person who was in the room. "Our whole goal was stop the train from moving that way."