The 44-year-old first female Alaskan governor was unflinching as she strode on to the party's national convention stage to a roaring standing ovation and set out to show she was the right choice as John McCain's running mate.
Skilfully balancing her toughness and femininity, Mrs Palin, who earned her nickname "Sarah Barracuda" through her tough games of basketball, said that, unlike Mr Obama, she had had "actual responsibilities" in the past.
"Here's how I look at the choice Americans face in this election," she said.
"In politics, there are some candidates who use change to promote their careers. And then there are those, like John McCain, who use their careers to promote change."
As she continued attacking her political rivals, Mrs Palin, who has described herself as a "hockey mum", joked that the only difference between a hockey mum and a pit bull was lipstick.
Referring to Mr Obama's experience in Chicago, she said: "I guess a small-town mayor is sort of like a 'community organiser', except that you have actual responsibilities."
To loud applause from the convention floor, she referred to Mr Obama's comments earlier this year that some voters in Pennsylvania were "bitter" and "cling to guns or religion".
"I might add that in small towns, we don't quite know what to make of a candidate who lavishes praise on working people when they are listening, and then talks about how bitterly they cling to their religion and guns when those people aren't listening," she said.
"We tend to prefer candidates who don't talk about us one way in Scranton and another way in San Francisco."
She went on: "We've all heard his dramatic speeches before devoted followers. And there is much to like and admire about our opponent.
"But listening to him speak, it's easy to forget that this is a man who has authored two memoirs but not a single major law or reform - not even in the state senate.
"This is a man who can give an entire speech about the wars America is fighting, and never use the word 'victory' except when he's talking about his own campaign."
Watched by her husband Todd, known as the "First Dude" of Alaska, and her family who have been at the centre of a political storm this week, the mother-of-five set out to dismiss questions about her experience, and about John McCain's judgment in choosing her, after a series of potentially damaging revelations.
Her unwed teenage daughter is pregnant, Mr McCain met the former beauty queen only once before making his decision, and her office is being investigated over the dismissal of a commissioner who refused to fire her former brother-in-law, a state trooper, following a messy divorce from her sister.
But she came out fighting with a speech which appealed to the Republican party's conservative base and which also highlighted her small-town values in a bid to woo some of Hillary Clinton's disillusioned former supporters.
Mr McCain's running mate also mocked Mr Obama for holding his convention speech on an elaborate columned-stage last week.
"When the cloud of rhetoric has passed, when the roar of the crowd fades away, when the stadium lights go out, and those Styrofoam Greek columns are hauled back to some studio lot - what exactly is our opponent's plan?
"What does he actually seek to accomplish, after he's done turning back the waters and healing the planet?
"The answer is to make government bigger, take more of your money, give you more orders from Washington, and to reduce the strength of America in a dangerous world."
She also criticised the media which has raised questions about her background and family and said: "I'm not going to Washington to seek their good opinion - I'm going to Washington to serve the people of this country."
Mrs Palin topped a night of attacks on Mr Obama from Mr McCain's former presidential rivals, including former New York mayor Rudy Giuliani.
She also stressed her family values and said "no family ever seems typical".
"That's how it is with us. Our family has the same ups and downs as any other, the same challenges and the same joys."
In an early indication of one role she may take on as vice president, Mrs Palin, whose youngest son Trig has Down Syndrome, said the parents of special needs children would have a "friend and advocate" in the White House if she was elected on the Republican ticket.
Away from the political rhetoric, millions of TV viewers saw her youngest daughter Piper, seven, cradle her four-month-old brother Trig while licking her hand and trying to pat down his hair.
Mrs Palin's oldest daughter Bristol, 17 - the centre of a media frenzy this week - held hands with her fiance Levi Johnston, 18, who flew to the convention from Alaska after the family announced Bristol was due to give birth to their baby in December.
The 18-year-old high school hockey player, who described himself as a "f*****' redneck" in an obscenity-laden entry on the popular networking site MySpace, wore a smart blue jacket and tie for his first appearance on the national stage.
Mrs Palin kissed Mr Johnston on the cheek when he joined her on stage, along with the other members of the Palin family, during a rousing standing ovation at the end of her speech.
Mr McCain also emerged from backstage to congratulate Mrs Palin and her family.
"Don't you think we made the right choice for the next vice president of the United States?" he said.
"What a beautiful family."
VIEW GALLERY
Comments