McCain (April 15): I propose that the federal government suspend all taxes on gasoline now paid by the American people -- from Memorial Day to Labor Day of this year. The effect will be an immediate economic stimulus -- taking a few dollars off the price of a tank of gas every time a family, a farmer, or trucker stops to fill up.

Clinton (from campaign Web site): Suspending the gas tax will provide real, immediate assistance to American families and for our economy. Recent testimony before the House of Representatives by the American Trucking Association indicates that even small changes in price can have big impacts. Just a one-penny decrease in the price of diesel annualized over an entire year would save the trucking industry $391 million a year.

Clinton campaign spokesperson Geoff Garin said in a conference call this week that the proposal would save each driver $70. The Clinton campaign did not respond to our request to clarify how it arrived at that figure. But the nonpartisan American Association of State Highway and Transportation Officials estimates that the total savings for the average American motorist works out to about $28; for a two-car household, that would be $54.

That's IF prices actually dropped 18.4 cents per gallon. However, there's every indication that they wouldn't. Here's why: According to the basic principles of supply and demand, cutting the price of an item causes people to buy more of it. That’s why stores put items on sale. But when something is priced too low, consumers will buy it faster than it can be manufactured, which leads to shortages.

For gasoline, this means that cutting the price by 18.4 cents per gallon -- even though that's only about 5 percent of the current going rate -- will likely stimulate demand for more gas, economists say. Unfortunately, there's not all that much more gas that can be provided to U.S. consumers. The refineries that turn crude oil into gasoline are already working at close to full capacity. According to the Department of Energy, U.S. refineries have the capacity to process 17.4 million barrels of oil each day. Since only about 46 percent of a barrel of crude oil is converted to gasoline, U.S. refineries, operating at their peak, can produce only 8.06 million barrels per day of the stuff most cars run on. But the DOE also says that the U.S. consumes 9.25 million barrels of gasoline per day. In other words, American motorists are already using about 1 million more barrels of gasoline per day than American refineries can produce.

With the supply of gasoline pretty much fixed (at least in the short term), the increased demand triggered by the price cut will lead consumers to bid up the price of gas. Len Burman of the nonpartisan Tax Policy Center says eliminating the federal tax won’t actually lower the price of gas because “supply constraints will push pump prices near their pre-holiday levels.” He goes on to warn that “if that didn't happen, there would be shortages.” The libertarian Cato Institute's Jerry Taylor agrees that a short-term gas tax holiday will have "little impact on pump prices."

For all the legislative prowess of McCain and Clinton, we’re doubtful that either candidate can rewrite the laws of supply and demand. That 18.4 cents per gallon won't go to consumers. Instead, the proposal will simply shift that money from government coffers to the oil companies. We're willing to grant that if the laws of economics themselves took a holiday and the price did drop that much, the amount saved might be meaningful to many motorists, particularly those who are low-income and those who drive a lot. And there would likely be all kinds of ancillary benefits involving price reductions for food and other products that have to be transported, as well as airline tickets and the like.

But we can't find any economists who think we'll actually see that drop in the price of gasoline. Others have tried and failed as well. And the Clinton campaign hasn't produced one, either.

Clinton (May 2): We have a choice. We can choose to have you continue to pay the federal gas tax this summer or we can choose to try to make the oil companies pay it out of their record profits...We ought to say: Wait a minute, we’d rather have the oil companies pay the gas tax than the drivers of North Carolina, especially the truck drivers, or the farmers, or other people who have to commute long distances.”

Bush (4/19): The Department of Energy estimates that ANWR could allow America to produce about a million additional barrels of oil every day, which translates to about 27 millions of gallons of gasoline and diesel every day. That would be about a 20 percent increase of oil -- crude oil production over U.S. levels, and it would likely mean lower gas prices.

Bush: I don't think it would affect price, for this reason: We're buying, at the moment, about 67,000 to 68,000 barrels of oil per day, fulfilling statutory obligations to fill up the SPR. World demand is 85 million barrels a day. So the purchases for SPR account for one-tenth of one percent of global demand. And I don't think that's going to affect price.

EIA: ANWR coastal plain oil production in 2025 is projected to constitute between 0.5 to 1.3 percent of total world oil consumption.

NY Times: The business of turning crude oil into gasoline, jet fuel or heating oil has rarely been a lucrative proposition. It has dismal profit margins compared with its more glamorous cousin, exploration. It is highly cyclical and fairly unpredictable, because demand for gasoline swings sharply by season.

Ten years after the company first decided to try to build the refinery and seek permits, it still lacks enough investors and hasn't begun construction.

Someone did get something right. Bush is correct in noting that the average price for a gallon of gas has climbed $1.40 in the last 18 months, from $2.25 to $3.65. So while politicians' solutions may slip on faulty reasoning, the problem remains a stubborn fact.

-- by Justin Bank and Joe Miller