By Wesley Johnson, PA, in New York
Sarah Palin, the first woman on a Republican presidential ticket, is John McCain's biggest gamble.
Her surprise selection reinvigorated the Christian conservative base of the Republican Party and she was hailed as a "breath of fresh air" in the campaign, widely reported to be wooing voters in battleground states with whom Mr McCain had struggled to connect.
But serious questions were raised about her lack of experience and Mr McCain's judgment in placing the state governor and self-styled "hockey mum" just a heartbeat from the presidency - at 72, he would be the oldest first-term US president and has a history of skin cancer.
After being largely hidden from the media for weeks by the McCain campaign, Mrs Palin took part in a series of disastrous TV interviews which saw her become a laughing stock on the national political scene.
Even some conservatives started to turn on her. Conservative commentator Kathleen Parker said her "cringe reflex" was "exhausted" and it was clear Mrs Palin was "out of her league" and should pull out of the race.
In the one-on-one interviews, she could not describe the Bush doctrine in foreign affairs - the six-year-old US policy of military pre-emption - seemed to have little grasp of the proposed financial industry bailout and even appeared to endorse Mr Obama's position on chasing al Qaida terrorists in Pakistan, a policy criticised by Mr McCain.
At one point, she suggested she was unsure what was involved in the vice president's role and struggled to name which papers she read, eventually saying: "All of them, any of them that have been in front of me."
Mrs Palin's answers have become punch lines for comedians, in particular when she cited Alaska's proximity to Russia when asked about her foreign policy experience, and a mocking impersonation by Tina Fey on the comedy show Saturday Night Live has become a television and YouTube sensation.
But in the only vice-presidential debate of the election, with expectations at their lowest possible level after a rough week for the Republicans, she produced a confident and sturdy performance, avoided any game-changing mistakes, and went some way to restoring a little of her damaged reputation.
Critics noted she refused to answer "too many questions", never really got beyond her talking points and got the name of the top US general in Afghanistan, David McKiernan, wrong, but she came across as "likeable" and could hold her head high again.
Still, her levels of support were a far cry from when she first stepped onto the stage and electrified the crowd at the Republican Party's national convention, receiving a roaring ovation as she portrayed herself as a pit bull with lipstick.
Skilfully balancing her toughness and femininity, Alaska's first female governor said that, unlike Democratic presidential nominee Barack Obama, she had had "actual responsibilities" in the past as she defended her experience. The high-profile speech came after a series of controversies stole the national and international headlines from Mr Obama as she joined the race to the White House.
It emerged her unwed 17-year-old daughter Bristol was pregnant, her office was being investigated over the Troopergate scandal, and Mr McCain met the 44-year-old former beauty queen only once before making his decision.
It was also revealed she did not have a passport until last year and had only travelled abroad on two occasions, once last year to Germany and Kuwait to visit Alaska National Guard troops, and once to Ireland.
To counter this, she was given a whistle-stop tour of world leaders when members of the United Nations convened for their annual General Assembly in New York last month.
During one meeting, Asif Ali Zardari, the president of Pakistan, called her "gorgeous".
Many US political pundits had ruled her out as a potential running mate for Mr McCain because her office remains under investigation over the dismissal of the state's public safety commissioner Walter Mondale who allegedly refused to fire her brother-in-law Mike Wooten, an Alaskan state trooper, following a messy divorce from her sister.
A legislative investigation into the affair is due to report later this month, shortly before the November election.
Mrs Palin, who was previously a small town mayor, is also younger than Mr Obama, and has just two years' experience in state office.
She is a pro-life devout Christian, a fiscal and social conservative and holds a lifetime membership with the National Rifle Association.
Mrs Palin also hunts, eats moose burgers, ice fishes, and rides snowmobiles.
She rose to attention in Alaska after blowing the whistle on ethical violations by state Republican Party leaders and was elected in 2006 after beating the incumbent Republican governor in the primary and a former Democratic Alaskan governor in the general election.
On April 18, Mrs Palin, gave birth to her second son, Trig Paxson Van Palin, who has Down's syndrome, after she refused to let the results of antenatal genetic testing change her decision to have a baby.
Born in Sandpoint, Idaho, on February 11 1964, Mrs Palin moved to Alaska with her family as an infant.
In the 1980s, she earned the nickname "Sarah Barracuda" for the intensity of her play as captain for the Wasilla High School Warriors basketball team in Wasilla, Alaska.
In 1984, Mrs Palin came second in the Miss Alaska beauty pageant after winning the Miss Wasilla contest earlier that year. She also won the Miss Congeniality award.
She has a journalism degree from the University of Idaho, where she also minored in politics.
Mrs Palin has also admitted using marijuana when it was legal in Alaska, but said she did not like it.
Her husband, Todd, the so-called "First Dude" of Alaska, is a Native Yup'ik Eskimo who works for BP outside the fishing season and is also a champion snowmobiler, winning the 2,000-mile "Iron Dog" race four times.
The couple, who have been married for more than 20 years, eloped after she finished college and reportedly recruited two residents from a nearby elderly care home when the pair realised they needed witnesses for the civil ceremony.
Their eldest son, Track, 18 at the time, joined the US Army on September 11 last year and is serving in Iraq. She also has three daughters - Bristol, 17, Willow, 13, and Piper, seven.Summing up her role in the race, she told conservative US talk show host Hugh Hewitt: "It's time that normal Joe 'six-pack' American is finally represented in the position of vice presidency."
