The Democratic presidential candidates’ heated rhetoric over the gas tax last month might lead voters to think the candidates are vastly different on energy and environmental issues. But removed from politics and campaign commercials, Sens. Hillary Rodham Clinton (N.Y.) and Barack Obama (Ill.) actually are virtually indistinguishable on everything from reducing greenhouse gas emissions to fuel standards.

Although neither campaign responded to inquiries for this article, a review of their Web sites and speeches offers a glimpse into the energy and environmental policies the Democrats would pursue.

Both promise to aggressively combat global warming and support a 100 percent auction cap-and-trade system — in which corporations pay for the pollution they emit, with the goal of reducing carbon emissions to 80 percent of 1990 levels by 2050. Money generated from the carbon permits would fund a host of alternative and renewable energy developments.

[IMGCAP(1)] Clinton and Obama also aim to drastically increase fuel-economy standards. Obama says he would roughly double standards, to 50 miles per gallon, by 2027, while Clinton would push them to 55 mpg by 2030.

With both candidates in lock step on those topics and on everything from conservation to biofuels to improving the energy efficiency of federal buildings, that leaves only the gas tax as a point of division.

[IMGCAP(2)] Likely Republican presidential nominee Sen. John McCain (Ariz.) originally proposed the idea of providing summer relief from the 18-cent-per-gallon federal gas tax, and Clinton quickly jumped on board. The issue played out in advance of the Indiana and North Carolina primaries, with Clinton charging Obama with being out of touch about the pain customers are feeling at the pump.

Obama responded by opposing the proposal as a “classic Washington gimmick” that would save the average consumer only about $30 for the summer — assuming oil companies didn’t raise their prices to cancel out the tax relief.

Regardless, the issue did not appear to be decisive, as Clinton narrowly carried Indiana and Obama cruised to victory in North Carolina, both as expected.

Clinton and Obama support ethanol — a political necessity in the first-to-vote state of Iowa — though on his Web site Obama warns of environmental hazards and higher food prices caused by increased ethanol production.

“The truth is, corn ethanol is neither the perfect nor the permanent answer to our energy challenge,” Obama said in October during his campaign’s major energy speech in New Hampshire. “Even if we double or triple its production, it won’t replace even a tenth of our demand for gasoline.”

Both candidates also hail cellulosic ethanol made from wood, grass or other plants as being better for the environment than corn ethanol. Obama would aim to get 2 billion gallons of cellulosic ethanol in the system by 2013. Clinton would raise the national renewable fuels goal eightfold, to 60 billion gallons, by 2030.

The candidates also are in agreement when it comes to modernizing the country’s electricity system, each pledging to generate 25 percent of electricity from wind, solar and other renewable sources by 2025. Clinton and Obama both pledge to “flip” the profit formulas for utilities through grants and other financial assistance, giving them incentives for energy efficiency rather than the number of kilowatt hours used.

Clinton and Obama both are wary of nuclear power and oppose storing it at Nevada’s Yucca Mountain.

And finally, in a constant of the entire campaign, they both ridicule President Bush, who has, they charge, “spent most of his time in office denying the very existence of global warming” — said Obama in his New Hampshire speech — and “systematically undermined our path to a clean energy future,” as Clinton put it in a November energy speech in Iowa.

Like most things in the energy and environment field, that’s something on which the two candidates can agree.