She's a former beauty queen, a fierce competitor known as "Sarah Barracuda," a political insider-turned-outsider and the first female governor of Alaska.

Now 44-year-old Sarah Palin, a mother of five who gave birth to her last child in April, could be a heartbeat away from the presidency, should her 72-year-old running mate win in November.

Not since George H.W. Bush plucked an obscure senator from Indiana, Dan Quayle, as his vice presidential selection 20 years has a running mate choice been greeted with such a loud and collective "Who?"

"She's not from these parts and she's not from Washington," is how Sen. John McCain, the presumptive Republican presidential nominee, described Palin, pronounced PAY-lin, as he introduced her yesterday in Dayton, Ohio.

"She stands up for what's right and she doesn't let anyone tell her to sit down," McCain said.

So it is with the former Sarah Louise Heath, the third of four children born to Chuck and Sally Heath, Chuck a teacher and Sally a secretary.

There's a storybook quality to Sarah Palin's life, a blue-collar tale of pluck, good fortune and independence. She grew up in Wasilla, a town of 9,800 near Anchorage, and was an aggressive point guard on her high school's state championship basketball team. In 1984 she was crowned "Miss Wasilla" and voted "Miss Congeniality," a title that would no longer fit once she entered elective politics.

After earning a degree in journalism from the University of Idaho, she eloped with her high school sweetheart, Todd Palin, a commercial fisherman, North Slope oil field worker and four-time state champion in long-distance snowmobile racing.

As a young mother, Palin launched her political career in 1992, presenting herself as a "new face, new voice" on the Wasilla City Council. Four years later, at age 32, she was elected the town's mayor.

Though she describes herself as an "average hockey mom," Palin has skillfully navigated her way through the rough and often corrupt Alaskan political thicket, striking an effective balance between self-promotion and challenging the Republican powers-that-be. In her speech yesterday in Dayton, Ohio, Palin came across as forceful, a trait that originally attracted her to the chieftains of Alaska's Republican Party, who arranged for her 2003 appointment to the Alaska Oil and Gas Conservation Commission.

Shortly after joining the commission, Palin led an ethics probe of the commission's chairman, Randy Ruedrich, who was also the state GOP chairman. Facing conflict of interest allegations, Ruedrich eventually admitted ethics violations and resigned.

Palin also joined an ethics investigation against Alaska's Republican attorney general, who had close ties to then-Republican Gov. Frank Murkowski. Suddenly, she was an outsider in her own party. But that paid off with corruption-weary Alaska voters, who liked her independence.

"She has very, very good political instincts," said Mike Kenny, former Alaska Teamsters union president and now a Democratic candidate for the state House of Representatives. Kenny, in his role as Teamster president, endorsed Palin in the 2006 gubernatorial primary, but does not call himself a supporter now.

"I think she's a mile wide and about an inch deep," Kenny said. "But she has the Alaskan touch — she's a hockey mom, she hunts, she fishes. Her husband is a man's man, her son joined the Army ... These are powerful images that resonate with a lot of people," Kenny said.

One potential blemish on Palin's record is an investigation into charges that she pushed early this year for the firing of an Alaska state trooper — her ex-brother-in-law — who was involved in a bitter child-custody dispute with Palin's sister.

There's no evidence yet that the charge has seriously damaged her. In the week before the Democratic convention, Hellenthal said, Palin's approval ratings were 79 percent, the highest of any Alaska politician in history.