Clinton goes on and on and on ...

WASHINGTON (AFP) — Deaf to pundits who think delusion, denial or unsated ambition are driving her sinking White House quest, Hillary Clinton is living out the lyrics of a campaign anthem, going "on and on and on and on."

Deep in debt, trailing Democratic foe Barack Obama in every meaningful measure of the race, the indefatigable former first lady will not lay down, even as the finish line looms on June 3, after three final nominating contests.

Going on, she is, but without Obama's crowds -- he pulled 75,000 to an event last week -- and deprived of the scent of victory which might ease the fatigue after a 16-month coast-to-coast nominating trek.

She has taken a political campaign further than any woman in US history, but now must endure the ignominy of being publicly pitied: even movie star Clint Eastwood said this week he felt sorry for her.

In another indignity, Clinton has seen her campaign compared in the Washington Post to the expired, "ex-parrot" in the famous Monty Python sketch.

With Obama, presumptive Republican nominee John McCain, and most of the chattering classes apparently convinced the race is over, Clinton has to answer the question of why she is going on, almost every day.

"We carry on this cause for a simple reason, because we believe the outcome of our elections should be determined by the will of the people -- nothing more, nothing less," Clinton said in Florida on Wednesday.

But the arithmetic is daunting. Clinton trails Obama in nominating contests, elected delegates, superdelegates, and the popular vote -- if you do not include, as she does, voided contests in Florida and Michigan.

But Clinton's campaign boss Geoff Garin insisted on MSNBC on Wednesday "the math is there" arguing that Clinton still had a chance at least of convincing top party officials she was the better general election prospect.

Political analysts believe that to be mere wishful thinking, so theories as to Clinton's motives are springing up thick and fast.

One thesis, borne out by events, is that the former first lady, a survivor of decades in the political crossfire, is simply not a quitter.

"Why she's still carrying on is pretty clear: it's the way she works as a politician and as an individual," said Marjorie Hershey, a political science professor at Indiana University.

"She is extremely tenacious. She is not easily deterred by opposition."

Clinton also clearly feels that despite her parlous political position, she would be the best president.

The New York Senator has piled up around 17 million primary votes, and feels a deep obligation to, and kinship with, her supporters, who often stop her with tales of deprivation and heartache.

"Any politician who comes this far and this close in the nomination process has a number of fervent supporters and those people would be very disappointed," Hershey said.

Some observers think Clinton may be hoping for a skeleton to tumble miraculously out of Obama's closet, something on the scale of racially explosive comments of his former pastor Jeremiah Wright which set back his campaign for weeks.

Others speculate that Clinton, and her husband former president Bill Clinton are so wound up in the fury of campaigning, they have not allowed themselves to think that her tilt at history is over.

Cynics argue Clinton is already plotting a 2012 presidential run, and needs as many votes as possible, to bolster her political prospects, should Obama lose November's election.

Darker theories still have it that Clinton's real goal is to damage Obama, so that he will lose -- and free up the party ticket four years hence -- though that idea lost traction a bit since she has eased her attacks last week.

And finally, could Clinton be trying to strengthen her hand should she wish to talk her way onto the Democratic ticket as a vice presidential nominee?

But, while everyone else is deserting her, Clinton, at least still stands by the title of that campaign song, a 1981 hit by Journey: "Don't Stop Believin."