ST. PAUL, Minn. -- John McCain's new running mate, Alaska Gov. Sarah Palin, has served in North America's largest oil region for the past two years, creating a complicated record on energy that is sure to raise questions about McCain's energy positions in the general election.

Palin supports offshore drilling like McCain, but they diverge on drilling in the off-limits Artic Wildlife National Refuge. She's for it and he's against it, although he's said he is willing to re-examine the issue.

They both oppose a national windfall profits tax on oil companies, saying it would hinder domestic production. But she raised taxes on oil companies in Alaska last year, arguing that her predecessor, Frank Murkowski gave them too many breaks.

When asked by FOXNews.com whether McCain's criticism of Obama's similar proposal to tax oil companies was a contradiction to Palin's actions last year, McCain campaign spokesman Tucker Bounds batted the question away.

It remains to be seen how much general-election ammunition this will provide Democrats, who are expected to debate Republicans on two facets of energy policy: whether to expand offshore oil drilling and whether to impose new taxes on oil companies enjoying tens of billions of dollars in windfall profits.

The Sierra Club, a leading environmental group, already has criticized Palin's record on the environment and McCain's decision to name her as his running mate.

"No one is closer to the oil indusry than Governor Palin, " Sierra Club executive director Carl Pope said in a written statement. "Along with her support for drilling in the Artic Wildife Refuge and off our coasts, she also opposes a windfall proft tax on the richest oil companies."

Pope termed McCain's pick of Palin the completion of his "race towards the Bush administration's failed energy policy," citing her opposition to listing the polar bear a threatened species.

"Senator McCain has lost any chance of having a balanced or moderate ticket with this choice and has instead opted for the same, business-as-usual reliance on the outdated oil companies that has been the hallmark of the Bush-Cheney administration," the statement continued.

But McCain's campaign says the selection of Palin reinforces the reformist bedrock of his candidacy.

"The primary interest and motivation of John McCain's candidacy is to reform government and change the way business is done in Washington," McCain spokesman Tucker Bounds told FOXNews.com. "If that upsets some people, so be it."

Far from being too cozy with oil companies, such companies have been "less than pleased with John McCain's political positions," Bounds added, citing McCain's vote against the 2005 Energy Bill. McCain has called that bill "irresponsible" in its concessions to business interests.

McCain also has a record of opposing efforts to open certain public lands to drilling and of supporting proposals seeking to tackle global warming.

But in June, he made a public split with environmentalists and reversed his long-standing opposition to the federal ban on offshore drilling. At the same time, donations to the McCain campaign from oil and gas industry executives and employees rose to $1.1 million to McCain in June, compared with $208,000 in May, and $283,000 the month before.

McCain's presidential opponent, Barack Obama, proposed a windfall profits tax on U.S. oil companies in June, saying he would use the tax revenues to help families pay for rising energy costs and other bills.

McCain slammed the proposal, saying that the tax would be passed on to consumers, raising prices at the pump even more.

"For Senator Obama, the solution to every problem and the answer to every challenge is a new tax," McCain said at the time. "And he is convinced that a 1970s-style windfall profits tax is just what America needs in the 21st Century.

"Now as then, all a windfall profits tax will accomplish is to increase our dependence on foreign oil, and hinder exactly the kind of domestic exploration and production we need. I'm all for recycling -- but it's better applied to paper and plastic than to the failed policies of the 1970s."

Palin also opposes the windfall profits tax on the national level, though she made a proposal similar to Obama's last year when she introduced a state-based graduated tax pegged to increased oil prices, earning a repuation as a crusading reformer. The state legislature modified her proposal to increase the state's cut even further.

Alaska collected an estimated $6 billion from the new tax during the fiscal year that ended June 30, according to the Alaska Oil and Gas Association. That helped push the state's total oil revenue -- from new and existing taxes, as well as royalites -- to more than $10 billion, double the amount received last year.

The Associated Press Contributed to this report.