Washington - Barely a month after her spectacular entrance into national politics as the Republican vice-presidential candidate, Sarah Palin has gone from shaking up the campaign to being the preferred object of mockery of critics around the United States.

"Pathetic," one commentator called her on CNN. "Governor, bow out," wrote another in Newsweek.

The histrionic TV satire Saturday Night Live is enjoying a second youth based on imitating the Alaska governor.

Following just three interviews over one month, it is understandable that the campaign staff of Republican presidential hopeful John McCain has made Palin almost unavailable for the media: she clearly seemed to have serious difficulties expressing her political views.

Fragments of the latest interview, last week on CBS, are still being replayed on all TV channels. In them, Palin at times sounds incoherent, incapable of making complete sentences and of answering questions directly, other than with a series of unrelated campaign statements.

What exactly did she mean when she mentioned Alaska's proximity to Russia as foreign policy experience?

"It's very important when you consider even national security issues with Russia ... as Putin rears his head and comes into the airspace of the United States of America. Where - where do they go? It's Alaska."

Why should the government spend 700 billion dollars to bail out Wall Street instead of giving the funds to ordinary citizens?

"Ultimately, what the bail-out does is help those who are concerned about the healthcare reform that is needed to help shore up our economy, helping the - it's got to be all about job creation, too, shoring up our economy and putting it back on the right track. So healthcare reform and reducing taxes and reining in spending has got to accompany tax reductions and tax relief for Americans."

The effects of her few television appearances are proving devastating for her candidacy.

When John McCain surprisingly chose her as his running-mate in late August, most analysts saluted the choice of a young woman with fresh ideas. Now, as the country awaits her debate with Democratic vice-presidential candidate Joe Biden Thursday, views are just the opposite.

One opinion poll by television channel CNN showed that 49 per cent of US citizens think she is not prepared to be the country's vice president.

The second-in-line is far from symbolic in a nation where 14 vice presidents have gone on to become one of its 43 presidents - eight of them due to the death of their boss. And the issue is more relevant than ever in the case of McCain, who would be - at 72 - the oldest man ever to be elected to the White House.

Even some of the most conservative commentators - for whom the choice was supposed to be particularly appealing - are openly showing their disbelief.

Joe Scarborough, on MSNBC, said Palin "just seems out of her league." Kathleen Parker, a columnist with the conservative magazine National Review, called upon the vice-presidential candidate to bow out of the race.

"Do it for your country," Parker asked.

Other commentators have been more condescending.

"Poor Sarah," Judith Warner wrote in The New York Times. "Palin's nomination isn't just an insult to the women (and men) of America. It's an act of cruelty toward her as well," she said.

Media analyst Howard Kurtz noted in The Washington Post that "some journalists say privately they are censoring their comments about Palin to avoid looking like they're piling on." However, it is comedians that are enjoying themselves the most.

"Every time they let her talk for more than four minutes, you can actually start feeling sorry for her," said Chris Rock.

In the meantime, the McCain camp is still trying to protect her and said Palin would leave the campaign trail Tuesday and Wednesday in order to prepare for Thursday's debate. Then, with millions watching live, Palin will be in the line of fire.