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 ago 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."
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, Palin came across as forceful, a trait that originally attracted her to the chieftains of Alaska's Republican Party, who arranged for her to be appointed to the Alaska Oil and Gas Conservation Commission in 2003.
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 Republican Gov. Frank H. 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.
In the sometimes Byzantine, old boys' world of Alaskan politics, Palin has benefited from being seen by her opponents as a lightweight.
"From the moment she began making her mark in ... politics, she was criticized for being too young, too inexperienced and too naive," wrote Kaylene Johnson in her friendly Palin biography, Sarah.
"Yet, time after time over the years, underestimating Sarah always proved to be a big mistake."
Marc Hellenthal, a pollster in Anchorage, said Alaskans like Palin because she has a reputation for "speaking her own mind and then worrying about whether it's popular afterward."
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 prior to the Democratic convention, Hellenthal said, Palin's approval ratings were 79 percent, the highest of any state politician in history.
Few anticipated the former small-town mayor becoming governor two years ago. And no one saw yesterday's announcement coming.
"Everybody's still in a state of shock," Hellenthal said.
Sarah Heath Palin
Born: Feb. 11, 1964, in Sandpoint, Idaho
Experience: Alaska governor since December 2006; unsuccessful run for Republican nomination for lieutenant governor in 2002; chairwoman of the Alaska Oil and Gas Conservation Commission, 2003-2004; served two terms as Wasilla mayor and two terms on the Wasilla City Council
Education: Graduated University of Idaho, 1987, journalism
Family: Husband, Todd; five children
Business: Worked as sports reporter for two Anchorage television stations; with her husband, owned a snowmobile, watercraft, ATV business from 1994 to 1997; her husband is a North Slope oil field worker
Source: Associated Press