That's a good question, considering he was running well ahead of all potential Democratic presidential wannabes.
A CNN-Time poll just last month found that 36 percent of Democrats nationwide preferred Gore. Not too far behind was Hillary Rodham Clinton at 20 percent. The other candidates didn't get more than single digits.
So Gore was clearly the front-runner for the nomination.
Did Gore pull out because he thought Bush would win easily in 2004?
Probably not.
In fact, Gore talked with NewsMax's Chris Ruddy and John LeBoutillier in New York last week and told them he had little doubt that Bush's popular support would collapse in the next two years.
Many Democrats remember Bush's father and his high midterm approval ratings after the Gulf War - ratings that turned into mush by Election Day.
Why, then, is Gore withdrawing?
One answer may be Hillary's efforts to block Gore's fundraising.
NewsMax, in a special report by Carl Limbacher, "Hillary Plans for the Presidency," detailed Hillary's behind-the-scenes efforts to lock Gore out of the Democratic money machine.
The report detailed how Hillary had quietly been sidelining New York and Hollywood big-money Democrats, the base of the party's money machine, telling them not to donate to Gore and await either her decision to run or go with another candidate.
Also, the DNC's apparatus remains firmly under the Clintons' control, with the DNC headed by the Clintons' handpicked DNC chief, Terry McAuliffe.
Gore must have clearly seen that his efforts to raise money would be stymied by Hillary.
Even after McAuliffe's and Hillary's debacle this past Election Day, McAuliffe and the Clintons remain firmly in the driver's seat.
In fact, they believe the Democrats have nowhere else to go.
Without Bill or Hill, who will draw a crowd in New York or Hollywood?
As detailed in the Special Report on Hillary's presidential plans, Hillary has long had a distaste for Gore and his wife, Tipper.
The dust-up between Hillary and Gore began on the day Bill Clinton was inaugurated. Secret Service overheard the Clintons in a screaming match. Hillary was demanding to occupy the vice president's office, next to the Oval Office.
Things between Gore and Hillary never improved.
Gore has told associates he blamed Hillary for his loss in 2000.
Gore claimed that Hillary's Senate run pulled precious White House and DNC resources, not to mention national media attention, from his campaign.
Editor's note: There's a lot more about the behind-the-scenes effort by Hillary to gain the presidency. Find out about this in Limbacher's special report, including new details that Hillary may wait until the last minute and run as vice president in 2004. Also, Dick Morris, one-time Clinton confidant, reveals Hillary's presidential plans.
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