By ELISABETH BUMILLER

WASHINGTON - Three years ago, Carleton S. Fiorina was the celebrity chief executive officer who was spectacularly fired by the Hewlett-Packard board. She produced a best-selling memoir, “Tough Choices,” but for the most part spent the years after her ouster in relative self-imposed exile from public life.
No longer. Ms. Fiorina, known as Carly, is back, this time reincarnated as a bold surrogate for Senator John McCain.
On television, Ms. Fiorina praised Mr. McCain’s fund-raising prowess with the announcement that he had raised $21.5 million in May. She pushed Mr. McCain’s proposal for a gasoline-tax holiday and ignored the fact that she could not name a credible economist who supported it.
In the months before that, Ms. Fiorina tirelessly promoted Mr. McCain’s economic proposals .
“When people were picking apart our tax cuts and saying, ‘This will cost a gazillion dollars,’ she’s very good about saying, ‘Come on, guys, let’s get the numbers and push back,’ ” said Mark Salter, one of Mr. McCain’s closest advisers. “She’s a very smart woman.”
Ms. Fiorina’s official title is chairwoman of the Republican National Committee’s “Victory ‘08” committee dedicated to electing Mr. McCain as president, and she is typically described as an economic adviser to the candidate. To some extent, she is. But Mr. McCain’s campaign advisers say her real role within their circle matters more: A high-profile female face for a candidate whose support among women lags substantially behind that of his Democratic rival.
“She has a great feeling for the economy, for technology and probably what women think about these things, and she’s wired in,” said Thomas J. Perkins, a pioneer venture capitalist and a leader on the Hewlett-Packard board in Ms. Fiorina’s ouster.
In turn, a number of Republicans say Ms. Fiorina is using the McCain campaign to rebuild her image after her explosive tenure at Hewlett-Packard. They also say it is hard to see why a woman widely criticized for mismanaging one of Silicon Valley’s legendary companies is advising a candidate who acknowledged last year that he did not understand the economy as well as he should.
“Well, see, the good news about business is, results count,” Ms. Fiorina, 53, said. “And the results have been very clear. The results have been crystal clear. From the day I was fired, every quarter, even before they had a new C.E.O., has been record after record. That doesn’t happen unless the foundation’s been built.”
Opinion is still split on whether Ms. Fiorina or her successor as chief executive, Mark V. Hurd, deserve credit for Hewlett’s success after Ms. Fiorina drove through the company’s $25 billion acquisition of Compaq in 2002. By many accounts, Ms. Fiorina was superb at marketing, mixed on strategy, bad at execution - and very successful in unifying the board against what Jeffrey A. Sonnenfeld of the Yale School of Management calls her “street bully” leadership style.
“What a blind spot this is in the McCain campaign to have elevated her stature and centrality in this way,” said Mr. Sonnenfeld, the senior associate dean for executive programs at the management school . “You couldn’t pick a worse, nonimprisoned C.E.O. to be your standardbearer.”
But Mr. McCain, as Ms. Fiorina put it, does “clearly not” share the views of her critics.
In the meantime, Ms. Fiorina has done little to tamp down speculation that she might run for office herself, including the California governorship in 2010. “I would be disingenuous if I said it has never occurred to me,” Ms. Fiorina said about running in general. For now, she said, “I’m focused on getting McCain elected.”