Palin says the US should drill its way out of dependence on foreign oil [GALLO/GETTY]

Sarah Palin, the governor of Alaska who has shot to prominence as John McCain's choice as running-mate, is best known as a passionate believer in new oil and gas exploration, including in Alaska's National Widelife Reserve - something McCain himself rejects.

But campaigners say she has a mixed record on her dealings with the oil corporations to which the Republican party has so many historic ties.

"There is no question that Palin's appointment as the Republican vice-presidential candidate cements the fact that John McCain is the candidate of big oil," Dan Weiss, a senior fellow at the Centre for American Progress, a Washington-based think-tank, told Al Jazeera.

"She supports the agenda of big oil - of more drilling - and she opposes investments in clean and renewable energy," he said.

Palin has presented herself as a challenger to corporate interests in Alaska, although that is because she believes the major energy companies have not acted swiftly enough in carrying out drilling and pipeline projects in the state.

Ending dependence

McCain and Palin have considerable ties to big oil firms [EPA]

"I beg to disagree with any candidate who would say we can't drill our way out of our problem," she told Investor's Business Daily magazine earlier this year.

In 2006, she acted to renegotiate a deal with Exxon, BP and Conoco Phillips to build a pipeline carrying natural gas from Alaska's North Slope region across Canada to the US.

Palin also pushed for legislation to provide $500m in state funds to the companies to act on the project and eventually agreed to give the contract to TransCanada, a Canadian firm.

She also introduced a new tax on oil companies operating in Alaska and went as far as saying she supported Barack Obama, the Democratic candidate, when he proposed a windfall tax as part of his energy policy earlier this year.

However, her husband, Todd Palin used to work for the British Petroleum oil corporation in Alaska's North Slope region and she has collected almost $13,000 from lobbyists connected to the oil industry, reports say.

And Matt Gonzalez, environmentalist Ralph Nader's running-mate for his presidential campaign in 2008, says Palin has characterised the windfall tax in different ways depending on the audience and that she has not taken on oil corporations in the way she has claimed.

"We know that the oil companies have been making profits that have never been seen before, and the taxes that Palin has introduced are trivial in comparison," he told Al Jazeera.

Environmental concerns

Palin has opposed rulings on designating polar bears as endangered [EPA]

"A changing environment will affect Alaska more than any other state, because of our location. I'm not one, though, who would attribute it to being man-made," she said in an interview in August this year.

Palin, a keen hunter, has also threatened to sue the US government over its ruling on having the polar bear designated as an endangered species and opposed protection for salmon threatened by pollution from the mining industry.

The Palin connection has worried campaigners already concerned about McCain's ties to large oil firms that have led to him being dubbed "Exxon John" by Democrats.

McCain has received more than $1.5m from oil and gas interests for his presidential campaign, nearly four times more than the amount Obama has taken, according to figures up to July from the Centre for Responsive Politics.

Lobbying power

At this year's Republican National Convention, the power of the oil lobbying firms was on display.

In focus

In-depth coverage of the US election

Randa Fahmyhudome, a former Bush administration energy official, said Palin was right to call for drilling in the Arctic National Wildlife Refuge.

"In America, we are world's number one consumer of petroleum in the world and no-one knows better than Alaskans themselves what is good for environment. We ought to look to Alaskans and Governor Palin on this issue," she said.

"New technology will help us protect the environment while we develop these resources," she added.