WASHINGTON - MR OBAMA'S fist bump. Mrs Palin's lipstick. Mr McCain's plumber. Mrs Clinton's tears.

We've been through a lot in the two-year slog that will be remembered as Campaign 2008.

Much of it was temporarily fascinating. And at the same time utterly forgettable.

What will endure? What will fade faster than a campaign promise? The answers depend, in part, on who wins on Tuesday night.

If Mr Barack Obama becomes president, he and Michelle may soon be fist-bumping on the White House portico.

If Mr John McCain pulls out a victory, Tina Fey's spot-on send-up of Republican running mate Sarah Palin could well be 'the iconic image of the 2008 election', says Professor Robert Thompson who teaches pop culture at Syracuse University.

Even if Mr McCain loses, the Fey factor may well have some legs.

What does it say that, in the end, one of the most enduring images of the campaign may be a comic's schtick about a vice-presidential candidate? Already, so much of what we've talked about, blogged about, analysed and dissected is fading from memory.

Remember the mini-tempest over Mr Obama's lipstick-on-a-pig comment, and whether it was a subterranean insult to Mrs Palin?

Or Mrs Hillary Rodham Clinton's gripping account of her arrival in Bosnia under sniper fire, which never happened?

Or Mr McCain's ad lumping Mr Obama with Britney Spears and Paris Hilton as just another celebrity?

Or the video of Mr John Edwards carefully coifing his hair, set to the music of I Feel Pretty? We're just getting started.

There was Mr Obama's Jay-Z moment when he brushed off his shoulders, giving a visual brush-off to his critics.

And Mr Joe Biden's putdown of former New York Mayor Rudy Giuliani's speeches as nothing more than 'a noun, a verb and 9/11'. There was Mrs Palin's eye-popping announcement during the Republican convention that her unwed teenage daughter was pregnant.

And will.i.am's viral Internet paean to Mr Obama, Yes We Can, featuring celebrities like Scarlett Johansson and John Legend.

There was Mrs Clinton's doomsday ad claiming she was best equipped for the 3am phone call.

And Mr McCain's Web ad mocking Mr Obama as 'The One'. (Complete with images of Charlton Heston as Moses parting the Red Sea.)

There was Mr Obama dancing his way onto the set of The Ellen DeGeneres Show. (Mr McCain did Ellen, too, but he didn't dance.)

And Mr McCain planting himself on the couch with the ladies of The View. (Mr Obama did The View too.) There was the Republican convention chant of 'drill, baby, drill'. And the Democrats' rejoinder of 'jobs, baby, jobs'. Mr Obama had Obama Girl.

Mr McCain had Joe the Plumber.

Remember Mrs Clinton choking up in New Hampshire about what was at stake in the race, and later declaring that was when she'd 'found her voice'?

Or Mr Biden waxing on about President Franklin D Roosevelt's TV presence during the 1929 stock market crash - when FDR wasn't president and there wasn't any television? Or martial arts star Chuck Norris barnstorming for Mike Huckabee? Mike who?

Prof Thompson offers an apt oxymoron for it all.

'They were temporarily iconic.'

You betcha.

What will endure? Mr Obama's address on race, way back in March, could well stand the test of time, regardless of whether the Democrat wins or loses.

When his campaign was thrown off-stride by his former pastor's incendiary remarks about race, Mr Obama faced the issue head-on and spoke to the frustrations of Americans of all races: 'The anger is real. It is powerful, and to simply wish it away, to condemn it without understanding its roots, only serves to widen the chasm of misunderstanding that exists between the races,' he said.

Months later, the 84,000 people who filled Denver's Invesco Field to see Mr Obama become the first black American to accept a major party nomination for president were a sight to be remembered.

For Mr McCain, his most memorable moment may well have come far earlier, when he found redemption in the snows of New Hampshire after losing the Iowa caucuses. His candidacy had been written off not much earlier as essentially dead.

Mr Eric Dezenhall, a public relations expert, nominates a different telling moment for Mr McCain, from the town-hall-style debate in October.

'He was sort of wandering around in the back as Obama was speaking,' Mr Dezenhall said. 'You have this old guy who just doesn't know what to do.'

The victor's path to the presidency will be well chronicled in future history books.

The losers' treks, no matter how compelling, will get lesser treatment. Except, perhaps, for Mr Obama's historic journey.

For all of the intensity of Mrs Clinton's quest to become the first woman president, from the dramatic high of her New Hampshire comeback to her excruciatingly long exit from the race, and all of the drama and silliness in between, says Prof Thompson, 'ask any 18-year-old freshman entering college five years from now about any of those things and I will be very surprised if any of them can tell you anything.' -- AP

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