Record-high prices for gasoline, heating and electricity and growing concern about global warming have pushed energy issues to the forefront of the 2008 presidential campaign.

Not since the gas lines of the 1970s has energy loomed so large as it does in the race between Republican John McCain and Democrat Barack Obama, says Kenneth Medlock, an energy expert at Rice University. And it's an issue that is unlikely to fade between now and November.

While the candidates agree on a few energy-policy issues, such as not drilling for oil in the Arctic National Wildlife Refuge, they are far apart on others. McCain, for instance, is more supportive of offshore drilling and strongly favors nuclear power. Obama envisions a bigger role for government in the nation's energy future, seeking to invest billions in new technology while mandating stronger fuel-efficiency and alternative-energy standards. McCain wants to rely more heavily on existing laws and market forces.

Both candidates, meanwhile, are far more willing than President Bush to tackle global warming by imposing new fees on greenhouse gas emissions.

Consumers, who are reeling from high energy costs, will be watching to see how any action may hit their wallets.

"The prices are completely outrageous," says Amanda Browning, 31, of Detroit. Browning, a single mom who is at home taking care of her two children and 87-year-old grandfather, says it's not just about cost. She's concerned about energy's impact on the environment and the nation's reliance on foreign oil.

No matter who wins, there is likely to be far more action on energy policy than in the past few presidencies as high prices and concerns about global warming push the issue to the top of many lawmakers' to-do lists, says Greg Valliere, chief political strategist at the Stanford Financial Group.

"Something is certain to happen next year," Valliere says.

OIL DRILLING

Both candidates have softened their positions

High energy prices have forced both candidates to soften their positions on oil-drilling restrictions, but they continue to disagree on the key issue of drilling offshore.

Obama says oil companies need to focus on drilling in areas already leased to the oil and gas companies and supports more drilling within areas, such as in parts of the Gulf of Mexico, where exploration and production is already permitted.

McCain advocates a complete lifting of the ban on drilling in the Outer Continental Shelf.

Neither candidate supports opening up Alaska's Arctic National Wildlife Refuge to drilling.

ELECTRICITY

McCain wants 45 nuclearplants; Obama's skeptical

McCain is far more bullish than Obama on conventional electricity generation, especially nuclear power, as a way to meet soaring energy needs. McCain wants to build 45 nuclear plants — which emit none of the greenhouse gases that cause global warming — by 2030. That's ambitious. Until recently, no company had filed an application for a reactor since the 1979 Three Mile Island meltdown.

Obama, by contrast, says that before the nation builds a new generation of nuclear reactors, issues such as the security of nuclear fuel and where to store waste must be solved. Some say he's paying lip service to a vital energy source.

The candidates also differ on coal, which supplies 50 percent of U.S. electricity but accounts for 40 percent of carbon dioxide emissions, the chief greenhouse gas. Both want to develop technology to capture and store carbon dioxide from coal plants. McCain, though, says the U.S. should continue to build coal plants meantime. Obama says new coal plants must be designed to permit retrofitting of carbon-capture devices when the technology is available in a decade or more.

GLOBAL WARMING

Similar strategies, but Obama's more aggressive

To combat global warming, both Obama and McCain want to impose new constraints and fees on companies that emit carbon dioxide. But Obama's plan is more aggressive.

Obama wants to reduce emissions 80 percent below 1990 levels by 2050 — the amount the Intergovernmental Panel on Climate Change, an international monitoring group, says is needed to prevent a worrisome rise in global temperatures late this century.

McCain was one of the first Republicans to break with his party several years ago and introduce cap-and-trade legislation. But now he's calling for more modest carbon dioxide reduction than Obama: 66 percent below 1990 levels by 2050.

PRICE RELIEF

Obama wants tax credits paid for by oil companies

McCain and Obama have deep differences on delivering relief to U.S. consumers slammed by the rapid rise in energy costs.

Obama advocates tax credits of $500 for an individual and $1,000 for a married couple making up to $150,000 to help offset higher costs for gasoline, heating and other costs. The rebates, which would go to approximately 150 million Americans, would be paid for with a windfall tax on oil company profits. McCain is opposed to a windfall tax, arguing it would discourage investment.

McCain during the summer supported the temporary repeal of the federal gasoline tax of 18.4 cents per gallon as prices at the pump broke records. That proposal is tabled for now as the summer driving season has ended. Obama is opposed to the repeal of the federal gasoline tax, arguing it doesn't provide much relief to consumers and reduces a key source of funding for roads and other infrastructure.

CARS

McCain wants big fines on carmakers with low mpgs

Each candidate would use tax credits to promote higher-mileage automobiles. Obama would require manufacturers to meet higher mileage requirements, while McCain would increase the punishment for automakers that fail to meet the current mileage standard, known as Corporate Average Fuel Economy, or CAFE.

CAFE is the average miles per gallon of a manufacturer's entire fleet manufactured in the USA.

Obama proposes increasing the U.S. fuel-economy standard by 4 percent per year in perpetuity. The increases would lead to 49.5 miles per gallon by 2025, up from the current 25.

McCain backs raising the penalties for violating the existing CAFE standard, but does not support increasing the miles-per-gallon requirement. McCain also proposes a $5,000 tax credit for a zero carbon-emission car, such as cars that are battery-powered. He does not advocate mandating that all cars run on alternative fuels.

RENEWABLE ENERGY

McCain pushes for tax credits to fuel innovation

Everyone loves renewable energy, and Obama and McCain are no exceptions. Obama, though, has a more aggressive plan for expanding the role of renewables, while McCain espouses a more market-based approach.

Obama proposes spending $150 billion over 10 years for development of wind, solar, geothermal and other renewable energy, including advanced transportation fuels like cellulosic ethanol, which is made from grasses and plant waste. That, he says, would create 5 million jobs.

McCain is less precise, proposing a tax credit for companies doing research on renewables equal to 10 percent of their employees' wages.