Here is a surprise....
One answer may be Hillary's efforts to block Gore's fund raising.
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' hand-picked 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.