She arrived in a blaze of glory and at a stroke injected new life into John McCain's presidential election campaign like a dose of political viagra.
But one month after Sarah Palin was unveiled as the shock Republican vice-presidential pick, the surge of populist momentum provided by the Alaskan governor's elevation to national politics is waning, analysts say.
On Thursday, the photogenic 44-year-old mother-of-five faces the biggest test of her campaign so far when she goes head-to-head in a debate with her Democratic opposite number, the vastly experienced Senator Joseph Biden.
The showdown comes hard on the heels of a faltering performance in a prime-time television interview with CBS anchor Katie Couric last week, and at a time when even conservative commentators are questioning her credentials.
Professor Jack Citrin, professor of political science at the University of California Berkeley, said Palin had been remarkably successful in "mobilising and energising" support since her appointment, but interest was now cooling.
"She was an interesting new face in a kind of politics where celebrity, status and media attention is important," Citrin told AFP.
"Her views and self-presentation appeal to a component of the Republican Party coalition that were not so enthused about McCain.
"But the focus has turned now to figure out what she really knows and what she doesn't know, especially in the context of an economic crisis where people are anxious and alarmed," he said referring to the Wall Street meltdown.
Palin's interview with Couric -- only one of three the McCain campaign has granted to media since her unveiling -- reinforced scepticism surrounding the candidate's ability.
As well as stating -- without explaining how -- that Alaska's proximity to Russia had given her useful foreign policy experience, she said US forces had secured "victory" in Iraq, a bolder assertion than even McCain has offered.
Republican strategist Tony Fabrizio told Politico.com that Palin's interview was cause for concern. "You can't continue to have interviews like that and not take on water," he told the website.
The performance also drew a withering review from prominent pro-Republican columnist Kathleen Parker, who wrote in the National Review that Palin was now such an embarrassment to the party that she should step down.
"Palin's recent interviews with Charles Gibson (ABC News), Sean Hannity (Fox News) and now Katie Couric have all revealed an attractive, earnest, confident candidate. Who Is Clearly Out Of Her League," Parker said.
"As we've seen and heard more from John McCain's running mate, it is increasingly clear that Palin is a problem," she added.
A CNN/Opinion Research Corp survey last week suggested that 49 per cent of voters believe Palin lacks the leadership qualities required in a president.
However, for some analysts, Palin's limited experience in foreign affairs is unlikely to affect her support among the rank-and-file Republican base, which responds to her staunchly conservative views on abortion, guns and religion.
"The party base doesn't care about foreign policy, so it should not be too much of a concern," said Sherry Bebitch Jeffe, a political analyst at the University of Southern California. "But the media love affair is over."
And Jeffe said she believed it is doubtful that Palin may be able to attract undecided voters or former women supporters of defeated Democratic hopeful Hillary Clinton.
"There's no question she's injected the Republicans with an enthusiasm that John McCain could not," Jeffe said.
"Having said that, she hasn't been able to reach out to Hillary voters in any circumstance. And I think she's probably caused some of the independents and undecideds to think twice about her in the past couple of weeks.
"The polls now indicate that a majority don't think she's ready to be President. And that's not helpful."
Citrin meanwhile said McCain's advanced age -- at 72 he would be the oldest man ever elected to a first term as president -- meant more attention than normal was being paid to Palin's level of experience.
"Let's face it, you really don't need to know that much to be vice-president," Citrin said. "But when the president is a 72-year-old man the stakes are higher than they normally would be."
AFP