Having invested 16 months and raised more than $200 million in the campaign, Clinton may find it difficult to quit. Her campaign persona is now built on the idea that she's working-class America's scrappy warrior. So dropping out with six contests left in the campaign season would be awkward.
And those who have spoken to her say she is reluctant to leave.
Rep. Tim Mahoney (D-Fla.) met privately with Clinton on Wednesday at the Democratic National Committee's offices in Washington. "She wasn't talking exit. She's talking winning," Mahoney said.
Chris Lehane, who served in President Clinton's administration, said: "Having worked for them, I would never, ever count out a Clinton: Bill, Hillary, Chelsea or the cat, Socks. One of the primary reasons she has remained extremely competitive in this race is that people have extrapolated she's a fighter."
But even trusted aides don't see how she can wrest the nomination from Obama.
They are divided over what course she should follow. Some believe she should not drop out until the last contests on June 3. Others contend she should exit "gracefully" sometime this month.
Ultimately, an aide said, Clinton will decide with her husband what to do; staff won't be consulted on so momentous a decision. The aide and others associated with the campaign requested anonymity because they were not authorized to speak for the campaign.
Some members of Clinton's circle are thinking through the conditions under which she might concede the race.
One supporter familiar with the campaign's operations said that Clinton wanted to go out on a positive note -- say, after winning in West Virginia and Kentucky, whose primaries are May 13 and 20, respectively.
She also would want a resolution to the disputed elections in Florida and Michigan, the campaign supporter said. That would enable her to say she worked successfully to give those voters a voice.
The Democratic Party nullified the outcomes in Florida and Michigan as punishment for their leapfrogging other states on the election calendar. Clinton won both elections, but neither candidate officially campaigned in the two states, and Obama's name wasn't on the ballot in Michigan.
On Thursday, Clinton sent Obama a letter asking him to help her ensure that Florida and Michigan voters "have a voice in selecting our party's nominee."
